That surprises me. Normally file conversion leaves the original file as it is and offers you the option to save the new file, the conversion, with a name and at a location you prefer.

Are you saying that this converter, (which one and the link to it please), actually incorporated those files into a video?

If so, and if the originals are gone, I see little that can be done. What did the software makers say when you told them about this?

Hopefully you still have your backups available.

Mark