Crash when importing Alembic data with a large number of vertices if Merge Meshes is enabled.

1. Import the attached abc file into the engine.
   The file was uploaded to a box due to its large size.
   [Link Removed]
2. If you change the import type to skeletal and import the file, it will be imported successfully.
3. Import with Merge Meshes enabled causes a crash.

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION writing address 0x0000000000000020VCRUNTIME140
UE4Editor_AlembicLibrary!FAbcImporter::CompressAnimationDataUsingPCA() [D:\EpicGames\UnrealEngine-4.27\Engine\Plugins\Experimental\AlembicImporter\Source\AlembicLibrary\Private\AbcImporter.cpp:958]
UE4Editor_AlembicLibrary!FAbcImporter::ImportAsSkeletalMesh() [D:\EpicGames\UnrealEngine-4.27\Engine\Plugins\Experimental\AlembicImporter\Source\AlembicLibrary\Private\AbcImporter.cpp:552]
UE4Editor_AlembicImporter!UAlembicImportFactory::ImportSkeletalMesh() [D:\EpicGames\UnrealEngine-4.27\Engine\Plugins\Experimental\AlembicImporter\Source\AlembicImporter\Private\AlembicImportFactory.cpp:260]
UE4Editor_AlembicImporter!UAlembicImportFactory::FactoryCreateFile() [D:\EpicGames\UnrealEngine-4.27\Engine\Plugins\Experimental\AlembicImporter\Source\AlembicImporter\Private\AlembicImportFactory.cpp:149]
UE4Editor_UnrealEd!UFactory::ImportObject() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Editor\UnrealEd\Private\Factories\Factory.cpp:201]
UE4Editor_AssetTools!UAssetToolsImpl::ImportAssetsInternal() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Developer\AssetTools\Private\AssetTools.cpp:2095]
UE4Editor_AssetTools!UAssetToolsImpl::ImportAssets() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Developer\AssetTools\Private\AssetTools.cpp:1303]
UE4Editor_AssetTools!UAssetToolsImpl::ImportAssetsWithDialog() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Developer\AssetTools\Private\AssetTools.cpp:1136]
UE4Editor_ContentBrowserAssetDataSource!UContentBrowserAssetDataSource::OnImportAsset() [D:\EpicGames\UnrealEngine-4.27\Engine\Plugins\Editor\ContentBrowser\ContentBrowserAssetDataSource\Source\ContentBrowserAssetDataSource\Private\ContentBrowserAssetDataSource.cpp:1789]
UE4Editor_ContentBrowserAssetDataSource!TBaseUObjectMethodDelegateInstance<0,UContentBrowserAssetDataSource,void __cdecl(FName),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:611]
UE4Editor_ContentBrowserAssetDataSource!FNewAssetContextMenu::ExecuteImportAsset() [D:\EpicGames\UnrealEngine-4.27\Engine\Plugins\Editor\ContentBrowser\ContentBrowserAssetDataSource\Source\ContentBrowserAssetDataSource\Private\NewAssetContextMenu.cpp:398]
UE4Editor_ContentBrowserAssetDataSource!TBaseStaticDelegateInstance<void __cdecl(void),FDefaultDelegateUserPolicy,TDelegate<void __cdecl(FName),FDefaultDelegateUserPolicy>,FName>::ExecuteIfSafe() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:731]
UE4Editor_Slate!SMenuEntryBlock::OnClicked() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Framework\MultiBox\SMenuEntryBlock.cpp:1081]
UE4Editor_Slate!SMenuEntryBlock::OnMenuItemButtonClicked() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Framework\MultiBox\SMenuEntryBlock.cpp:1032]
UE4Editor_Slate!TBaseSPMethodDelegateInstance<0,SMenuEntryBlock,0,FReply __cdecl(void),FDefaultDelegateUserPolicy>::Execute() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:290]
UE4Editor_Slate!SButton::ExecuteOnClick() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Widgets\Input\SButton.cpp:385]
UE4Editor_Slate!SButton::OnMouseButtonUp() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Widgets\Input\SButton.cpp:304]
UE4Editor_Slate!SMenuEntryButton::OnMouseButtonUp() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Framework\MultiBox\SMenuEntryBlock.cpp:400]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_cc5aea9e7377b04ce85c30c65ec3889b> >() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:378]
UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:4831]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5372]
UE4Editor_Slate!FSlateApplication::OnMouseUp() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5337]
UE4Editor_ApplicationCore!FWindowsApplication::ProcessDeferredMessage() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2205]
UE4Editor_ApplicationCore!FWindowsApplication::DeferMessage() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2698]
UE4Editor_ApplicationCore!FWindowsApplication::ProcessMessage() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:1881]
UE4Editor_ApplicationCore!FWindowsApplication::AppWndProc() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:905]
user32
user32
UE4Editor_ApplicationCore!FWindowsPlatformApplicationMisc::PumpMessages() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsPlatformApplicationMisc.cpp:125]
UE4Editor!FEngineLoop::Tick() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:4850]
UE4Editor!GuardedMain() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Launch\Private\Launch.cpp:178]
UE4Editor!GuardedMainWrapper() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:137]
UE4Editor!LaunchWindowsStartup() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:273]
UE4Editor!WinMain() [D:\EpicGames\UnrealEngine-4.27\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:320]
UE4Editor!__scrt_common_main_seh() [D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll