I actually wonder if he honestly doesn't know who Bryan Adams is. Despite his claims of being a musician/songwriter, his actual demonstrated knowledge of popular artists and songs seem to be about the length and depth of a small puddle. He's acting like Mr. Adams is some rando fan off the street/out of the crowd, and how dare he be able to get close to Tay-Tay when Russhole can't!
Then again, Russhole's ramping up obsession might simply have reduced him to a broken record at this point, repeating the same three things over and over: how he's currently suing her (despite still not having served her after months), how she's totally a bigot for not rewarding his 'gift' song with a shag and a lucrative songwriting contract (even though something isn't a 'gift' if you expect repayment), and how she slandered him (by honestly reporting her opinion about how she found his stalking and harassment of her and her family invasive and troubling).