I just don't see how the Reds get someone back as valuable as Gray. If you move Gray I think the team finishes below .500. Why would a team trade a young number 1 or 2 starter for Gray plus a franchise type of SS for Gray? That would be the only way a trade like that would make sense for the Reds, as without Gray your rotation is in shambles and it doesn't sound like the Reds have tons of money to spend to replenish it.
To me, if you move Gray that signals a rebuild. Just moving him and nothing else reminds of Cincy after 2013 until about 2015 where they were half in and half out, and ended up waiting too long to finally sell everything.