Recently scam OTC groups have been a lot be very careful about each group and make sure the group is real before you trade in it or use any of its escrow. if you see any new otc group which you see the first time there a big chance it's just an old scam group that changed the name.
Ive been into some OTC groups but never tried any of those yet. I think their modus is they have an inside man that will act as a mediator that will process some trades and suddenly will scam others showing there are some good deals. I like otc cause its benefit trader for cheaper price but if discovered a scam one that would be a messed up.
These groups should be reported via telegram. Once hit a good records they will marked it as scam or closed the group.