@Jesus ********
i'd say have them go wtih you to the immigration office with their lease, their thai i/d and see if they can file a TM30 in Section B on you. It's the same office as Section J, (right next to it almost 🙂 )
OR
slog on out there and try to get the extension without it.
I mean they might not ask, reports are they ARE asking but some people skate thru..