What's happening?

Based on your account, the core problem happening here is a term called "Deprotagonization". It's the fancy word for "What you're doing doesn't matter" which is one of the things the rules in the various Apocalypse World descended games is aimed to stop.

So, it sounds like he's violating several of the actual, rules of the game:

The GM’s agenda, principles, and moves are rules just like damage or stats or HP. You should take the same care in altering them or ignoring them that you would with any other rule. .... From the get-go make sure to follow the rules. This means your GM rules, sure, but also keep an eye on the players’ moves. It’s everyone’s responsibility to watch for when a move has been triggered, including you. Stop the players and ask if they mean to trigger the rules when it sounds like that’s what they’re doing.

Emphasis mine. It sounds like several of the moves you made as players did not get respected. When you do things that invalidate the possibility of a Player Move, you typically need to telegraph it or give some form of Soft Move. So things like having the growing wolf ignore the fire wall you've made doesn't work - it's not like it was a fire elemental or iron golem or something where you could reasonably say "Oh, fire doesn't work here."

Think dangerous

Everything in the world is a target. You’re thinking like an evil overlord: no single life is worth anything and there is nothing sacrosanct. Everything can be put in danger, everything can be destroyed. Nothing you create is ever protected. Whenever your eye falls on something you’ve created, think how it can be put in danger, fall apart or crumble. The world changes. Without the characters’ intervention, it changes for the worse.

A key point to this rule is that it's part of what allows player protagonization. A regular issue in railroading, and here, by your account, is when the GM protects their characters, their setting, over player actions. When, as the GM, you think of things as targets, as disposable, you stop protecting them and the players are free to have their characters do what want to do - and thereby be the center of the story.

So, that's the core of what's happening.

Talking to your friend, the GM

Now... here's the hard part. I don't know your GM, I don't know his personality or the best approach.

To be quite honest, most people I know who read the rules that spell out very clearly that there's a different approach and show no sign of having tried anything different? Those people are usually not open to change or criticism. This has been my experience over 2 decades of gaming.

It would be different if you were telling us he did differently than normal and had some fallback moments. But by your account, it sounds like he skimmed the rules, didn't read them, read them without understanding, or read them and consciously chose to throw them out - none of which indicate a person who's absorbing new ideas at all.

If you're going to do this, you should have the rules at hand. You should point out where things in the game worked different than what the rules say and point out that it explicitly says that these are "hard rules", not simply a "style of play". That choices to change the rules FROM that, are in fact, things you need to talk to the group about before play, and not simply surprise them with it.

If your group is otherwise solid, you may want to make this a group discussion, since the rules explicitly point out that it's everyone's job to make sure the rules are being followed... though if no one else spoke up in play, I'm guessing there's social dynamics at hand that may mean they're not willing to speak up or tend to avoid social conflict among the group rather than resolve things.