I faced an issue with a syntactically correct font. For some reason that font can not be loaded by Windows, telling it is a corrupt font file.
When I am building ots using Visual Studio 2019, meson and ninja locally, I am getting an error from ots-idempotent.exe:

• Failed to verify the original font

Which is correct in my oppinion.
When I am running the same using the supplied ots binaries for v9.0.0, no error is printed out, nothing.
It is using a method named VerifyTranscodedFont to load the font, which is implemented depending on the platform.
Does your version prefer the freetype instead of the Windows rendering engine ?
FreeType is able to render fonts, even if Windows is not able to load them.