This is... odd, to say the least. Honestly, I've never actually seen that part crack like that before in any of our testing, even in cases where the knob was tightened too much. It's a really durable part (you can pretty much stand on it), so this is rather surprising.
During testing, we even had an Atlas get hit by a falling tree and receive barely any damage (even the wind cups survived!). Though, we didn't build it with that level of heavy attacks from angry foliage in mind, so I wouldn't recommend trying it... but it holds up well regardless.
Furthermore, that mysterious blue goo is not something we recognize at all. I believe you're sending that one back, so we'll look at it here.