Working on a new lighter custom pack for the EOD team. I ran across this issue where either Biome Bundle or OTG is generating game save data under the mods folder. In the image below I created the game "Biome Bundle Testing." As you can see from the image it created a directory under mods\OpenTerrainGenerator for the game save as well as the normal save location.

Versions:
Forge: 14.23.1.2582
Biome Bundle v6.1
OTG v4

The files in the mods folder are not game save data, they are OTG config files for the biomes and bo3s.