Dealing Grubauer to a team before the expansion draft is a way to get a crummy return for Grubauer AND then lose another useful player (Schmidt) in expansion. The goalie market is going to be flooded before the expansion draft. Bishop is a UFA, Pittsburgh needs to move or buy out Fleury, Halak is the odd man out in Long Island, Mason is a UFA, and Colorado may try to get rid of Varlamov to protect Pickard. It's going to be hard to get the type of value they want for Grubauer until the market settles down after the expansion draft.
None of those G's you mentioned offer any real bang for the buck. Bishop is bound to get overpaid, Fleury is already overpaid, Halak and Mason are both "meh" with a capital M. Varlamov is the only real one that any team is going to want, especially Vegas....and he has his warts. And would cost more in $$$ thsn Grubauer.
It will really boil down to what George wants. If he wants Grubuaer bad enough, he could easily take Orpik in a separate deal with an assurance we leave Grubauer available. If he doesn't, then we see what the market is for Grubs, and allow him to take someone else, like Schmidt or Wilson. Or they stand pat and try to deal Orpik elsewhere, and lose Grubauer anyway.