Yep, all-in-one kits are not meant to be taken apart (at least the ones from Corsair). There's really no way to get it out, but you can try to change the positioning (put the radiator below (if it's above the CPU currently) the pump/CPU) to make the air bubble move. That may or may not help with your temps, but if it does, you can be sure that the issue is caused by a bubble.
After moving it a bit, the temps now sit at 85c (not much difference but thought I should report it) and neither pipe is hot, both seem to be working (based on vibrations) but I cannot hear anything.
(my computer is a fairly loud machine anyway
Yeah, it's probably dead. The heat is being transferred to the waterblock (since the other tube was originally hot), so it can only be an issue with the cooling system itself. It could potentially shorten the lifetime of the CPU in the long run, and it would cause the CPU to throttle to prevent burning itself to death, making it slower.
I would just get a new cooling system, or at least revert to the stock cooler (if you still have it) to keep your CPU at least somewhat cool.