Consider an offseason liner change this year. Liner changes from april to august are hard to come by, as all installers are slammed with work. Dont buy a new liner from anyone who tells you that wrinkles are common. Keep calling to find someone who cna get the work done for you.
I also had a tear along a bottom seam...I glued a round patch and fashioned a piece of 3/4 inch wood to just fit over the patch and set a ten lb rock on the top of it for 24 hrs, it did stop the leak.
Also to your side that has slipped out of the track at the top of the liner, I drained 5-6 inches of water just so I would have extra material to stretch and used a hair dryer
to heat the liner across a broad swath under the area that needs to be re-hung. This worked well and then I put in those pointed plastic shims made to pin liners in the track, that worked well also.