I tried to tell you on 27th sept via playstore review that the latest update of OBS studio i.e. OBS 32.0.1 and the one before it, lost the option to add droidcam as a source. Please check the images shared.
It also asks me to remove the droidcam obs plugin. Now tell us how to use this pro version with OBS. You got to do something cause this is impacting hundreds of thousands people, I am sure.
https://ibb.co/album/FgPfHD