Could my eggs be late bloomers ?

[XxPandaxX]

Hello all. I have been given 30 eggs to incubate. All the bantam eggs have been in constant hot temperatures - 102 degrees ! 2 less than damaging temps. Most of the time 98 degrees though. However, only 5 chicks are developing !! It will be day 7 on august 29. I've been instructed to leave them in till at least day 10 because some are slow on showing veins. I'm really worried because one has a suspiciously large moving black dot - the embryo- thats abnormal to the others.