I would let the PVC glue dry at least an hour or so. I have used it sooner. Not sure what caused the damage. Could have been freeze or the line might have been under stress from the beginning and finally broke. I would backfill with just dirt and whatever came out of the hole.
Easiest way to cut that PVC pipe is going to be a sawsall. But if that is not an option you could do it very slowly with any kind of hand saw like a backsaw (not a hacksaw!). Hacksaw blades will tend to wander and you won't get a straight cut with them. Specialized PVC cutters are hard to use above ground. Whatever method you choose it is a good idea to mark around where you will cut with a sharpie so you have guidelines all the way around the pipe.