ASFKAP, if the incident is as you described, I am a little mystified as to the need for an emergency descent. The Ryanair/Boeing procedures are to try and control the pressurisation in the first instance, and if that fails initiate an emergency descent.
Without going into the manuals ,am I not correct in saying that the outflow valve should have been controllable in Manual regardless of the glitch in the cpc ? ergo no need for emergency descent according RYR procedures.
It is always emphasised in training not to rush into an emergency descent ( nor indeed an evacuation) but to first try to control the pressurisation, and only if that fails initiate the "plummet". . . . Ha Ha.
I hope that was indeed the sequence of events here, as the previous Limoges incident "may" have ended with a precipitious evacuation given the absence of fire or any life threatening circumstances ( with the caveat here being that the report hasn't been published so that opinion is firmly in the "rumours" section of rumours and news )