Very good point. I went to Wally's and they didn't have it and said it is available online only. I found some caulk in the basement and filled the hole for now so it doesn't leak until the Eternabond arrives. Here is what it looked like:
It looks like the skylight expanded in the heat and shifted upwards between the screws and broke the seal. Further inspection found a small opening in the sealant around a waste vent. I poked at it and it turned into a large void! Looks like the applier stopped short and covered hios mistake. I also found gapa at the corners of the front cap. That's 1 sure leak and 3 possibles on a 1 year old camper!