That cut in the wood looks just like mine only they used the better Pex line marital so I think Im safe.
From the picture and knowing mine, it doesn't look like you have very good access. If you can get the wood panel off(the warranty shop will do this eventually) you could try Hurricane Tape. Most hardware stores sell this stuff for emergency repairs, they sell it in several strengths by the poundage. I always carry a roll for just an issue like yours.
I would pull the panel, disconnect the line from the potty, clean and dry very well and then straighten and wrap the Hurricane tape as tight as I could over lapping 2inches on either side, reconnect, leave the panel off and say a prayer. As I remember Hurricane tape isn't very sticky it bonds to itself with pressure so you have to pull it tight.
I probably would not leave pressure in the line. Use water when you need it and then unpressurize the line by opening a faucet.
Camping is fun
2011 Wildwood T26BHXL
2004 Yukon XL Denali
43yrs of camping; one lucky guy