I think the suggestions all lean towards replacement, a good idea.
I had a bag explode in an LS-4 too. Seventy liters in the cockpit
puts the CG a little too far forward to climb, or to keep the nose off
the runway at the end of the landing roll.
Replacing waterlogged electronics could be more expensive than
replacement of the bags. Somehow I was lucky and the radio survived
the underwater experience.
Time for new bags, the best you can get. Don't be tempted to buy
shower curtains whether paisley, daisy or other fashionable embossed
or printed design.
Do you have someone with thin arms to put the bags back in, Mike?
If the LS-4 hasn't already been converted to a 4a with larger bags,
now is the time if you can get the rubber baby buggy bumpers from DG.
Check TN 4018.
Jim

P.S. Having had an entire LS wing bag dump into my cockpit on course
during a contest years ago I'd endorse the suggestion of replacement
over repair. Funny the pressure trapped air can put on a sealed bag as
the altitude goes up.