It’s fairly likely the idea of disconnecting the AP was thought of and discussed during the incident; after all, the oscillations went on for some time.
You’re sat in the pilot’s seat of a fully FBW aeroplane, which develops an uncomfortable but contained roll oscillation with AP engaged. You’re climbing away from the ground and the wobbles appear to be getting neither better nor worse, giving time for some diagnosis/options/action. One possible scenario could be that there is a severe flight control issue which the AP and/or envelope protection is only just dealing with and going “manual” might make the situation worse or lead to LOC. There is always the pressure to DO SOMETHING but what if the cure is worse than the disease? The AP might readily disengage but not want to go back in...
I’m pretty sure that if the rolling had carried on after config. changes, at some point they’d have agreed to take the AP out. After all, landing in that condition is not going to be fun.