I don't know which comment you're referring to exactly,
https://gitlab.winehq.org/wine/wine/-/merge_requests/2091#note_23188
Sorry, now that I investigate more closely that comment was just wrong; WINE_NOTICE_WITH already checks that variable.
but you don't need the header and soname checks in the C code either.
Uhm, the soname makes sense, but how do I not need the header checks?
If the header isn't found, then you won't (can't) look for the library, and if the library isn't found, then the DLL won't be compiled.
Well, at least, that's the intent, but you've written "enable_vosk" as the fourth argument to WINE_NOTICE_WITH. You want enable_windows_media_speech.