If the are requiring all the normal information anything more then 5000 baht is too much. I could help with soft power for 4000 baht if you have 500K in bank
you don’t think they will pull people aside to show proof on there phone or print outs? My guess is something different in June or July what that is unsure. Plus, any odds of any officials watching these groups? Maybe an IO watched these groups for fun or information.
Others have done this. Not heard a problem yet. But you were allowed to travel anywhere but Thailand until approved. If the IO compares stamps to DTV it could be a problem but normally they are busy. Wait a month or till end of tourist visa and take a trip to Kuala Lumpur