Debo and Rocco- continue. Need behaviour explanation

Hi all, we are in the same place e with Debo and Rocco. Debo ignores him as much as he can and Rocco, all tho he calmed down a lot, he still wants to make Debo to be his friend. On the last walk we noticed that when Debo marks a place, Rocco will fallow and mark over it. On the other hand, if Rocco goes first, Debo will sniff it and walk away. Also we wanted to see how they going to act if we let the be in one room. So i walked Rocco in to his house put him in his crate ( the dog trainer suggested Rocco's house first, cause Debo has been in this house a lot before Rocco showed up). Then my oh brought Debo in on the lead. Everything was good,Rocco was sitting nicely in the crate,Debo had a sniff. He walked to Rocco's waterboy he sniffed it and walked away. From what i read only top dog will mark after another. And we thought it would be Debo. But maybe it's the other way around. Rocco is the top one, and Debo doesn't want to accept it and that's why we've got a problem? Any ideas?