Well, you are not completely out of bounds thinking it was a two-step process. That could be true if the compound indeed has to then be treated with an acid to form an electophile to go through EAS.
But the Pd(L2 HBr) is then going to react with the triethylamine present to regenerate the catalyst.
You need not be ignored, you post good stuff. We are conversating, bouncing ideas. To paraphrase Borek, I am occasionally wrong. This is how problems are worked through.