The Mayo Clinic runs different trials all the time that involve multiple biologics being used at the same time, AKA "off-label" and they can have great results for the individual. Rinvoq + Skyrizi is a newer combo, but it can be any number of them as different patient's disease can affect them more severely through different pathways.
If a medication combo is approved by a doctor for a patient, and they've even done the worthless dance that is required to try the drugs they already know aren't going to work, then the patient should be allowed it off-label. Especially so if it's proven to be working (lower c-reactive & calpro levels). Tapering off of prednisone in this situation is a massive success. You literally do not know if a biologic will work for a specific case of IBD until it is tried as each patient is different, at the same time these drugs all passed FDA approval and show stats of 40%+ remission after 12-18 weeks.
Also, medication like prednisone can't be prescribed long-term, massive health issues will follow like diabetes and bone density issues (among others highlighted by the article).