Correct way to add and confirm a User directly without having e-mail setup?+discussion
Yeah, when you invite someone. Whether the email gets out or not, they have a created account, so as admin you just change their password. IIRC, you go to their new user card, and navigate to Account->Details on the gear menu. Any admin can do this to reset any account pw manually at any time.
Same goes for requests, once you approve it, manually change it. Probably to a dummy one that you encourage the user to change themselves.