Best case scenario is that Buffalo doctors get convinced to approve the procedure, Eichel gets it, and trade talks are punted until he's able to start taking contact again.
The best case scenario is that he traded pre surgery, so they don't have to deal with the whole mess. Eichel will only get a greater return than now if he gets the surgery, gets back in playing shape, then plays a significant amount of games(at least 20) at a high level(PPG). I would guess the earliest that can occur would be in March, IF the Sabres ok ADR. At that time, you are also hoping that the few teams that are willing and able to trade for Eichel will still be able to do so. At that time, he will still not get full value in return because GM's will know that he has a neck issue that can reoccur at any time.
If Eichel gets fusion, then it is more likely that he won't be traded till the summer, but you'll be back to where you are now, except that it will be 1 1/2 years since he has played hockey, will do nothing but hurt his value. Complicating matters will be that he will have a NMC kick in.
I just don't get why the Sabres want to take the longest, most drawn out option to move Eichel. I do not see that he will get significantly more of a return if he is traded during the summer with very few, or no games played under his belt. I would argue that he will get the same as has been offered this summer, if not less, as he will have burned off one year of his prime, and his contract. Also, all this controversy about the types of surgery has to be giving GM's cold feet, no matter what procedure is eventually chosen.
All in all, someone has decided to be very stubborn, rather than smart. I sense a lot of ego in this, which makes me wonder if the Pegulas aren't involved in the decision making. In that case KA would have to stay tight lipped (which is smart)....I mean what's he going to say? My boss wants to make an example of Eichel, even if it hurts the team?