Hovabators are not very accurate and are known to flucuate alot. I would get a cooler and some flexwatt and a good thermostat and make a much better incubator.

Also your eggs look almost buried in vermiculte, I would think they are getting too wet and the temps are probably all over the place.

I ahve used a hovabator once for beardie eggs(and will never do it again) but would never use one for BP eggs.