Hello!
I believe this started in the incremental update that fixed the tarnished exploit. I didn't notice it before that in U41. I use Sharp as a tank companion. It's not great because he stands in stupid but for daily IA runs, he speeds the run nicely by letting my NB flanking passives buff my damage. Since the update I referenced, he never gains aggro. It's not that he loses it, he never gets it. It's like his "Provoke" skill is not working at all. Please fix Cyro crashes first, but this needs a look.