NWF,
Sounds like you have done all the right things. You only put brood comb in the Nuc. Being a Nuc, you reduced the size, and the box is full of bees. The bees can handle the SHBs, remove the eggs and larvae as long as there are enough bees. They should not have any problems especially since you found the queen. A lot of the brood get damaged during a cut out so do not worry about that. The bees are being hygienic. That is a good thing.
Jim Altmiller