If there were 4 people on-camera there were at least 40, if not more, off-camera. Remember somebody is shooting the video of the camera crew. There was an ambulance/medevac helo standing by I guarantee you. No production company would take a chance with a celeb of Ferrell's standing otherwise, whether you think he's funny or not. When actors talk about not being allowed to do certain stunts due to "insurance", they're telling the truth. The cost of something going wrong on a film or a television show is way too high to risk these days to let untrained actors do anything really dangerous.

Maybe so, although even with more support people they appeared to do some risky things, unless those were staged. Like the short rope maneuver with Will leading Bear down an icy slope, unless they staged that on the base of a slope it was definitely risky, they were crossing without crampons with a tired non-expert actor across a legitimately icy slope. Maybe Bear had a secret belay on? Who knows.

I could see this level of prep: scout the terrain, and run the sequence of necessary death defying events past Ferrell's people. Will gets a week to practice his repels and belays, and maybe a weekend to march around in the snow during daylight hours. The crew decides what additional safety measures to take so he avoids any obvious and deadly falls. Even then things go wrong - the belay out of the copter sure started out badly.

At minimum you're left with a long weekend trudging through deep snow and with a couple belays thrown in - had to be exciting and exhausting from Ferrell's perspective.

It was definitely "interesting" to watch...

It was obvious that they had to set stuff up in advance... They wouldn't take any risk with him.

Bear said a hunter had left the caribou carcass for them.

The show was entertainment - it wasn't rolling on the floor laughing, but my family enjoyed it well enough.