Doubt buffalo does that.

Even if the value is fair. There is just no way buffalo takes on another winger and blocks the prospects coming up.

Especially one that will probably be a rental.

Wings have 75 thousand LD already and don't need anymore, so they pass and not close

Detroit has less than zero use for, or interest in Gryz. Look elsewhere.

Why on earth would Detroit trade for a LD?

We have the best and deepest prospect pool on that position in the entire league as it is.

You are both correct for both reasons, but that is a steal!
It would be very difficult to find a spot for all of the 25+ goal forwards:
As you both said Buffalo would be better off developing their own prospects and IMO we will the same Casey next year while both Peterka and Quinn will break out much the same way Dylan did this year.
While it is a bargain, Buffalo has wingers who can provide the same production as Jake.