Are you referring to where the shower surround (walls) meets the floor basin is where you saw pink fluid leaking out?
If the shower head hose was hanging straight down (nozzle then points sort of horizontal about 2 to 3" above floor) or close to it while you pressure pumped the pink stuff in, it can spray up into the air gap between the shower basin and the walls. Then it can be stuck in there from capillary action until it is pressed out, breaks tension and falls out or evaporates.
I do not know this is your issue, just saying this is a possibility as I have seen it with water. If you used the camper on city water, the entire system is charged under pressure. If you had a leak in the piping, after several hours there would be water coming out somewhere. Most likely under the shower, across the floor our down through the floor. You did not mention anything of a leak from that time.
This has to have something to do with the way you winterized the shower. Start by thinking where was the shower head when the pick stuff came out?
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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