App Validation failing on bare dylib due to “Couldn't find platform family for 'libopencv_world.4.1.1.dylib'”

We've been trying to submit an app linking against a bare dylib (that is, it's not part of a framework). It's by itself in the .app/Frameworks/ folder. But I get a rejection from App Validation:


Couldn't find platform family for "libopencv_world.4.1.1.dylib". Coulnd't find CFBundleSupportedPlatforms in the Info.plist or LC_VERSION_MIN in the Mach-O for path "/Users/…/Library/Developer/Xcode/Archives/2020-02-18/App Debug 2020-02-18, 04.14 .xcarchive/Products/Applications/App.app/Frameworks/libopencv_world.4.1.1.dylib".


The dylib is built for deployment on iOS 12.0 using iOS 13.2 SDK. It contains a loader command LC_BUILD_VERSION:


$ otool -l libopencv_world.4.1.1.dylib | grep -A4 VERSION
       cmd LC_BUILD_VERSION
   cmdsize 32
  platform 2
       sdk 13.2
     minos 12.0


Prior to iOS 12.0, the linker emits a LC_VERSION_MIN_IPHONEOS loader command.
It seems like App Validation is erroneously rejecting the binary, but is there something I can do to address this?