looking real good there.
LOL. Your plants are looking really good.

I think the Mystery nep from Lowes is either a Ventricosa or Ventrata

It should also be a very fast grower. Ventricosa and Ventrata tend to grow like weeds. In like a few months, you'll have to repot it.
I think they will. They look healthy to me.
The dark spots on the larger basal are probably due to stress from the shipping, but as long as the center of it stays healthy, the spotty leaf will open, growing out a new and healthy leaf.

That would Definitely be awesome. I always enjoy pics of Spectabilis. And when it flowers, if its either a Male or Female, I may have something interesting in flower at the time to make some new neat Spectabilis hybrids.