I think it would be Ok to leave your dens outside for summer, just as long as they are shaded.
My dens are outside all year under a pergoda, our summer is often over 100F with very low humidity. Our winters are wet cool, day temps 60- 70F and night 35- 50F.
As for the keikis, I usually leave them on the parent plant until they have enough roots, then they come off but I have been a bit lazy lately. My dens are happy either way.
They are my toughest orchids, I do very little for them and they are in spike now!