Again glad everything worked out, and that you had the support. You might wish to open a thread in Lessons Learned (In the AI section) if you haven't' to pass on information to others.
I know that some people put reg changes right up there with mask clear, in things they're not comfortable with (I'm not suggesting your wife is) It's good practice to swap to your alternate and back again on dives. Obviously to get practice and it highlights any faults you may not get at the surface. Better to catch things early.
I once had a wet breathe and swallowed a bit of water which closed my epiglottis (although I didn't realise this at the time) Even changing regs to my pony had no effect (which it wouldn't but that was my reaction) - What did confuse me was looking at 2 different SPG's each reading over 150 bar in each cylinder. I went vertical to head for the surface just finning, and at 30' the spasm cleared allowing me to breath, so I have some sympathy and understanding.