stupid question, but I've seen it happen. Is this epoxy specifically for aquarium use? Ive seen guys go to HD and get epoxy there and use it for their tanks without reading the lable. Some epoxies you get from HD say on the back not for aquarium use. Try running some carbon to help clean up any impurities. It may not be the epoxy that did this.
Run some carbon and polyp pads ,I never use epoxy <bad enff that the skimmer stops skimming when you put b-ionic or you hands ,JMO
maybe a small WC as well
I use two part all the time. Like you said, my skimmer goes nuts for about a day, then it settles back down. Maybe you got some kind of bad batch of two part. I've never heard of that, but we all know, stranger things have happened.