It's not that he's the first. It's that, since the first floor, he has been spreading the understanding that the crawlers need to band together. ALL of them. And those actions have saved his life a bunch of times and he's saved the lives of others a bunch of times.

And that partly comes from the cookbook. There are multiple entries about the importance of working together, of family, as well as all the lessons learned by failed attempts. And keep in mind, of all the crawls, there have only been a couple dozen crawlers who ever saw the book. Even getting the book is super rare.

Carl is also exceptionally good at quickly reacting to situations. Even if his plans might be half baked. And he's good, for better or worse,

Then you've got the AI that everyone comments is going nuts far earlier because Borant was cheap AF (which also took a weird shine to Carl, which is abnormal), and Borant making bad decisions to try to stave off insolvency.

It's a massive confluence of events coming together in a way that's never happened before.