I'm not sure I'd want "bottom-tier" coders period, even if it were bottom-tier Stanford grads, or bottom-tier Googlers. Bottom-tier is typically really bad.

That said, bootcamps (at least the ones with good reputations) are usually much more aggressive than colleges are about kicking out students who can't do the work or have serious attitude problems. So the floor is probably higher when it comes to bootcamp grads vs. CS grads.