I'm just saying, our staff wouldn't allow us to change who has firewatch at what times, or anything like that. Sometimes they made it where we had firewatch intervals of 1/2-1 hour instead of 2 hours. Hopefully, for your sake, he will be able to make a deal with others in his platoon.
In my case, if anyone was caught on firewatch for someone else, things were about to get really ugly for the entire platoon.
edit: Also, just so you know, I didn't get to see my girlfriend of 6 years at any point of OCS until graduation. I think this was better for our relationship, personally, because I realized that I took her for granted a bit. Just saying.