Update, yesterday evening, 36 hours after moistening the seeds, the score is:
Papaya 10/10
Godbud X Dreamweaver 0/10, and not even a sign of splitting.

I looked up the latter on the seedboutique forum, where the breeder has a grow log. Seems he did a run of 30,000 seeds of that cross, that he calls 'dream goddess', but had some temp issues during drying, and low germination. I read between the lines that that is the reson they're being handed out as freebies... um, nice freebie. I'll update of course if any do happen to pop!

Anyhow, the papayas are all in dirt: 50% perlite 50% composted manure/humus. I'm expecting that mix to be a little on the 'hot' side with potential for slight burn, but it worked out for the BOG stuff I popped last month- they did get a bit burned, but 100% of them outgrew it quickly and growth was explosive after that.