Bolded parts of my comments are what actually get to the point. The rest is extra
Is he eligible to be re-entered into the draft? Could that be it?
No he's not draft eligible. As North American junior, he missed his two year draft window.
He has never been on an NHL contract (as he gained his free agency by not being drafted during his draft window).
Typically UFAs can only sign a contract in a given for the current season. The new season begins July 1, so, say April 4 2017, a UFA either has to sign a deal that includes the 2016-17 season, or wait until July 1 to sign a deal starting in 2017-18.
For all UFAs who have never signed an NHL contract before, whether they are college, junior, or European signings (ie. Draft-related free agents; players unsigned after being drafted or who were not drafted) they have an extra window between March 1 - June 1 where they can sign for the upcoming season. If they do not sign before that window closes, they have to wait until July 1 like every other UFA. (NHL CBA 50.8 (d))
This window is there, largely just to make things neater. There is a lot going on in June for the League offices, without even discussing playoffs. Player awards are finalized, June 1 is when the NHLPA must have their insurance benefit modification requests submitted, prelude to free agency, buy-outs, arbitration filings, and of course the draft, among others.
So, they draw a line somewhere so they can have better internal organization. This allows them to get a better a picture of free agency and who is available, but most specifically it ties very much into creating a draft list.
A player who initially went undrafted but who still has remaining draft window counts as a draft-related free agent during the season and during the March-June window, but come June 1, they enter back into the draft. So since some of this "draft-related free agent" group can go back into the draft, they close the window such that the League can then have an internal list of all players available.
Closing the window prevents situations such as "With the 40th selection, Florida is proud to select Sasha Chmelevski AND announce the signing of Morgan Geekie to an ELC" and moreso to avoid situations like, "With the 119th selection the Chicago Blackhawks select Dylan Coghlan", "Ohh... sorry! The Vancouver Canucks submitted a SPC at 11:58:12 am, and you didn't submit your pick until 11:58:54 am! They beat you to it! Ineligible selection; pick forfeited!"
Someone correct me if I'm wrong, but if I remember correctly, even if he signs an AHL contract, he can still be signed away if offered an NHL contract.
Having said that, not sure who would offer him an NHL contract.
My understanding is that the standard AHL/ECHL contract includes an NHL-out clause (and ECHL often, but not always includes an AHL one). I can't find a concrete answer on that but that's what the general understanding seems to be, as well as my best interpretation of the PHPA CBA for players in the AHL/ECHL.
I have never heard of a case of an AHL player being denied an NHL contract, but I can imagine,
if it is not defaulted into the contract and a player fails to negotiate it in, then the player would have to request the AHL terminate his contract and the team would reserve the right to refuse that request. Again, I personally haven't heard of that though.
