I would translate this roughly as “What are you guys doing?! Didn’t I tell you not to stick together?!”
My issue is simply with the 言って at the end. I would have expected 言った or something like that, not just a loose conjunctive like this. I presume it’s some kind of very casual construction but I’d like to understand what it conveys exactly.
Ah thank you, I must have encountered that in the past without even noticing it because it seems fairly common, I’ll pay closer attention in the future. I assumed the ん was just the “explication” の and unrelated to what preceded.
