Thanks everyone for the advice! Sorry for late response, however lots going on with new house closing and prepping for the move out of state in a couple months.
I have realized that the neuter idea is a bad one. I will be able to expand their cage once we move and will try buddy bath and re-intros then. If that doesn't work, I will put them side by side. Since I now have two water bottles with the split, I will be sure to try two of everything also. I do only use multi entrance hidey's (corner cabin) and fleece forests.
They have never been big on floor time and only enjoy being held for brief periods. I have been swapping them between the two levels and I think they both enjoy that. I do pet them a lot in their open top C & C and do inter act with them all the time in the family room.
Getting a health check for Nugget is a good idea.