Yesterday I had the same problem with Scummvm or it did not recognize the games or it threw me to the main menu, I have to do a series of steps to avoid problems
Step 1: download the rom or roms that we want to play
step 2: go to this address https://www.scummvm.org/compatibility/ and check the full name and short name of the game, unzip the rom and rename it with the full name
step 3: with the full and short names taken from the url of step 2, with the text editor we create a file:
<folder>
<path>./full name/short name.scummvm</path>
<another infos here...>
<game>
<path>./full name</path>
<another infos here...>
step 4: save the file as a short name.scummvm and place it in the game folder
step 5: the game folder we give the extension scummvm leaving the full name.scummvm
step 6: we put the folder already finished in rom> scummvm and we restart Batocera
NOTE: the full name and short name information is extracted from the url indicated in step 2
