Ok I feel like I should chime in. I actually live in Pinedale and have spent my whole life in this area.
First things first, Yes the 90-2 is only valid for the portion of the unit west of 191 and the type 1 is for the east. The dates are the same for both.
Best meat cutter is Neal Nelson as others have already mentioned his contact info. Hog island is the other one that has the trailer at Daniel junction but they don't actually do the cutting there they take it up to their Jackson facility every night and cut it there. Due to this I have heard of people not getting back what they took in. I have no experience with them but that is what I have heard. I take all my stuff to Neal (I actually graduated high school with him) and have never had any problems.
I do not see any reason you will need a razor to hunt this unit. The Jonah field (gas field) takes up the majority of this unit so there are roads everywhere. You can get away from the gas field if you feel like as well though. Since it is your boy who has the tag and it is his first big game animal I feel like it will more than likely be a short hunt for you. There are a LOT of mid 70s bucks out there and if you really want to trophy hunt there are some low 80s bucks out there too. I killed a 83" goat out of there with my bow a few years back.
I would recommend Pinedale for a place to stay. We have more options and are just a 20 minute drive down to the unit. There are also a lot more places to eat here as well. The lake that was referred to I am sure was Fremont Lake which is just a couple miles outside of town (12 miles long, 4 miles wide, and 700ft deep). There is also Boulder Lake, Half Moon Lake, Burnt Lake, Meadow Lake, Willow Lake, Soda Lake, New Fork Lake, and Green River Lakes just to name some of the larger ones. All of them have good fishing in them as do all of the rivers and creeks around here. If your hunt is short and you want some tips on where to fish just hit me up. You may also want to bring a smaller rifle to shoot prairie dogs since there are some large towns of them out in that unit (I was just out shooting them on Sunday).
Don't overthink this hunt, with a rifle you can be done within an hour if you want to be. Great first hunt for a kid. Have fun! Feel free to hit me up for any specifics.