Looks to me like your paper towel is way too wet. Ive had problems in the past trying many of the germination methods mentioned on all the forums. For the last few grows I have stopped doing anything extra, I just place my seeds directly into the soil(tip down) and just keep the soil wet. I have had 100% success since with about 5 dozen seeds so far. Works the same for hydro, just go straight into the rockwool but keep it in a sealed container to retain moisture until it pops up.