I love the subtle foreshadowing of Paperboi telling Darius to pass the joint to Earn, the same way Paperboi passed the joint to Darius at the start of the season after those two were beefing. I knew right then that all was forgiven between Paperboi and Earn even if Earn didn't see it.
Also, Earn had ulterior motives. I don't think it was even by accident that he brought the gun, I think what his uncle said about "needing it for the music business", he finally understood its purpose and wanted to set Clark up (or at least the manager would do) simply because he didn't want to be in the outs. He knew County Clark was in the way, and Paperboi was talking with his manager. In the first episode, he told his uncle of his eventual fear of Paperboi would fire him because he was no longer needed. So, I think that whole gun swap was premeditated. I just did not think he thought that Clark was going to play it off like he did and have his manager take the fall instead. Either way, it was a win for Earn, because he damn sure wasn't trying to lose his spot. That's why that whole shyt didn't faze him nor why he didn't panicked like we normally see him in tight situations.