I'd re-check her crop first thing in the morning, if it's not emptying, then begin treatment.
With her having a prolapse, some swelling, etc. this can slow the digestive system down, so hopefully once the prolapse has corrected itself, the crop problem will resolve too, but it won't hurt to...
I'm glad she laid a nice solid egg, that's great!
As for keeping her in the dark garage to stop production, a hen would need to be in total darkness for 16hrs a day for several weeks to stop laying eggs.
But! Sometimes when they are not feeling well, being in a place that quiet and dim can...
X2
Keeping the tissue moist if very important.
The urates will often stick to the tissue like glue it seems. Keeping the oil/ointment on there will help.
Daily soakings and see if it will heal up.