I don’t think taking the floor panels up will get you where you want to go. I had a similar Livewell on an older 22 tournament, and access to the connections was a pop out on the front of the helm passenger seat base. Are you able to check to see if your hose connections are leaking?
That livewell is on the rear transom deck area. Aren't there storage compartments below the livewell? You will have to remove the insert to see the bottom of the live well I think
My live well is under the passenger helm seat there is a pop out there but it takes a mirror to see and with My short arms I can't reach it. It looks like the hose fittings is leaking by looking on the mirror.
It is very possible that you will have to cut a hole in the deck. The hole would be the correct size to later install a deck inspection plate. The trick is figuring the best spot to cut the hole.