You can measure the soil temp with a kitchen thermometer, which I agree
is probably the problem. Grass needs soil temps in the 50s to
germinate. Don't worry about it rotting, you may have been a little
early, but it's better to be early rather than late. The 5-7 days that
was given as amount of time to germinate is for fescue or rye grass.
Blue grass can take 2 weeks plus. Did you put down some starter
fertilizer? Check and adjust the PH? For watering, no need to over do
it, you just need to keept the upper soil layer constantly damp. That
means watering several times a day for brief periods, more frequently
if it gets hotter. Then as the grass grows, over time you want to go
to less frequent, but deeper watering