Wait, what happened? Why did Jimmy react like this?

So we know how in season 5 Howard offers Jimmy, who is now back as a lawyer as Saul, a job in HHM. Jimmy of course takes this very badly, and starts with the screwing Howard thing (the bowling balls, the prostitutes, etc)

Now I've always assumed this comes back to season 1, in Pimento, where after discussing the Sandpiper case, Howard tells Jimmy that they just want the case, but HHM won't be hiring him. Jimmy of course gets extremely offended by this:

Jimmy: -I walk in here with a multi-million dollar class action lawsuit on a damn platinum platter. A case that I found, that I made happen. And you don't want me? [...] Someone walks in with a case like this, you beg them to be partner!

So when after years, Howard offers Jimmy a job at HHM, I thought Jimmy took it badly because it pissed him off that, now that he is very successful as Saul Goodman, only now Howard wants him at the firm. Like if Howard wanted to take advantage of Saul Goodman's branding, if you will.

The thing is, I'm rewatching the show and I'm seeing and remembering how in the next episode after Pimento, which is Marco, Jimmy and Howard do have a nice and chill talk where Howard tells him, is not that I didn't want to hire you, is just that Chuck is very important to the firm and I kinda had to do as he told. They both know it was Chuck's call, not really Howard's, and Jimmy shows that he knows and is not really mad at Howard anymore.

So why did Jimmy get offended when Howard offers him the job in Season 5? This was the first time Jimmy was a lawyer AND Chuck wasn't a part of the firm anymore (because well, he is dead), so, it was the perfect time for Howard to finally hire Jimmy! He didn't really want to take advantage of the Saul Goodman success, I think it's more like he can finally do what he couldn't really do in Chuck's time. Don't you think?

I don't know, maybe I'm wrong, what do you guys think?