Stubborn young male pitbull.

*** Before this gets automatically taken down we are NOT using dominance method to train our dog. *** Me and my boyfriend recently got a dog from a girl on Facebook. He is a 1.5 year old fixed and fully vetted male pitbull his name is king we had a 9 yr old pit male named moe already, and king is CONSTANTLY obsessed with him. He’s hovering him all the time, licking his back hovering over his back in the position like he’s about to hump him or does just try to hump him. Never leaves him alone. Constantly terrorizing him not even in a playful way, but in a constantly asserting dominance way. We can’t give him back to the owners and we want things to work with him but he does NOT take no for an answer for shit. He doesn’t listen and doesn’t leave Moe alone when moe is trying to set boundaries. He has 0 boundaries. We’ve tried everything. Verbal “no, leave it, leave him alone, go lay down” we’ve tried crating him or “place” command when he’s just NOT leaving him alone which he’s still struggling with place command. We’ve tried keeping them separated but king just jumps over gates or any barrier we’ve put in doorways. He gets destructive if tied up or closed behind doors. I hate having him in his crate all the time. I’ve had to legit shove him away from moe sometimes coz he will not respect his boundaries at all. Even when moe has attacked him over it, he either stops for 2 seconds and instantly starts up again or has attacked back and pinned him down. He knows he’s younger and stronger than moe and is constantly trying to intimidate him We really aren’t having this shit though. We don’t wanna give him up or anything already it’s only been a little over a week. Any advice at all? Desperate atp.