Sounds like you figured out how to get the "clip" off!
Heliocol calls that part the Latch. They don't seem to have a separate name for each half of it. Are you saying you broke "B" off of "A"?
If so, I wouldn't leave it like that. The Latch (A) is held onto the Panel Clamp with friction. It's doing all the work of maintaining the necessary pressure on the o-ring to complete the seal. So you're good-to-go in terms of fixing the leak. But it's part "B" that is keeping the Latch from popping off.
Don't forget, the entire array and all its components are under constantly changing temperatures, 24/7, all year long: expanding and contracting and sliding around the roof. And also that, if you've got an average size array up there, it's probably getting around 40GPM of flow. Which means, if that Latch pops off and the joint opens up, it'd only take about 5 hours to drain your entire pool onto your roof. Of course, that would only happen if your pump didn't starve and burn itself up first, when the water level drops below the skimmer mouth, which could happen in as little as 15 minutes or less!
So either replace the entire Latch, or find some other way to secure the Latch (A) in place. I'm thinking a length of stainless steel wire could do the trick. Don't use a zip tie, it'll rot and break with all that UV up there, and won't last long.