Hello, I decided to update the build of mods to 1.19 and found that on the new version your mod cannot detect ffmpeg. I checked ffmpeg with the old version and everything was fine.

Have you made any progress on solving this? The code for detecting FFmpeg is identical in both builds - if it is actually broken on 1.19 for you, it's most likely a compatiblity issue.
Cheers

Has any found a solution to this yet? I am assuming that ffmpeg should go into the .minecraft directory.

Yes it should, you can follow this tutorial to get it installed in general. Otherwise, simply placing the ffmpeg.exe into your .minecraft folder will do the trick. Given that the original issue has now been stale for well over a month, I'll go ahead and close it
Cheers