The en banc seems to be a longshot(although there's really no downside to trying). It seems they'll only grant it in cases where it conflicts with 10th circuit precedent(there isn't any on point), SCOTUS precedent(nothing on point), or other circuit precedent(perhaps Moore, which was absent from the opinion). I also looked at the current numbers on the circuit. All active judges, plus senior judges on this panel are part of the en banc vote. Assuming one of the judges here doesn't turn around and vote to rehear their own opinion, it would involve getting at least one Obama/Clinton appointee to vote for rehearing. I have yet to see(someone correct me) ANY Dem appointed judge rule for our side in any way shape or form.
The main problem here is that the court didn't fully address the whole complaint. Whether this was Gray's fault or the court's I don't know.