Caribou are our primary quarry, so I can speak with modest expertise. They roam huge, remote areas. When they get close to a road, in season, they attract a lot of road hunters. He can gamble, so to speak, on a road accessible hunt, such as 40mile herd near Steele or Taylor Highway, or Nelchina herd along Denali Highway. He might see more hunters than caribou, or maybe not. Let's call it a 50-50 chance at seeing 'bou. This is definitely the cheapest option.
He could drive up the Haul Road and hunt within 5 miles either side of it (the Dalton Hwy Corridor), but he'll see others and he's limited to Archery gear. He could hike across the corridor then hunt outside it with a rifle, but now he's got to get his camp and meat back to the road. This is doable, but a tough haul. If he's a soldier, he's probably in shape to do this, (motorized land vehicles aren't allowed in the corridor).
Similarly, it he got a tag for unit 13, he could hike/pack off the Denali Hwy into the Clearwater Controlled Use Area, and get away from lots of hunters. I think the application period for 2023 unit 13 caribou tags may have passed, but I'm not sure. Perhaps this is a 2024 option.
He could also get dropped off in a remote spot via airplane. This isn't cheap, but gets you away from road hunters. There are charter operators that do drop hunts out of Tok for the 40mile herd, and Deadhorse and Happy Valley for Arctic herds. I'd guess that there are charter operators that drop hunt SW Alaskan herds from Anchorage, perhaps McGrath, Bethel, or King Salmon, but I'm not certain.
His fitness is probably his strongest asset here. Most hunters aren't willing to walk very far from their truck/boat/4wheeler, and less willing to pack meat back. A fit adult can pack a boned out caribou in 1 or 2 loads, depending on terrain. I can't do it anymore, but I have done it many times before.
Hope this helps