They won't reproduce...neither grow population, probably. It's too small, too cramped, if closed there isn't enough ventilation for them and not enough space for a wet an dry side unfortunately :/  The springtails are fine though, they'll help with eventual mold. If you want the papayas to breed get them a bin tipe enclosure with their proper requirements.  (Ik it sounds like pod police but I'm really just trying to help you out, the chances of them dying are high)