Yes, that is possible, but you have to use your clinical judgement.
Maybe try whether the patient can finger occlude first? I have used RMT with patients with a trach and I have them finger occlude while they do the Breather. It's real easy to take their hand off if they start to feel panicky or short of breath. This is a great way to increase respiratory muscle strength towards goals of using the Passy-Muir valve, or goals of capping the trach, or eventual goals of discharging.
The use of RMT is very appropriate here. It’s important to have your tools on hand to monitor vitals, and checking in with the patient on how they're feeling.