Recruiters work on commisions (so they only make money when they place one specific candidate), so if you seem like you're just going to drop out later, you are essentially just costing them monymoney.
If you have many questions that aren't easily answered by the job description itself, the recruiter may forward them on to the hiring manager via email. Remember, the recruiter makes money from placing you. They likely forwarded your question as soon as they got it rather than it being buried, unless they have moved on. However the recruiter usually has very little intricate knowledge of the position itself, and will have to forward this question out to the hiring manager and wait for their response.
The hiring manager will take a while to respond.... I don't know about you but every manager I've ever had has been absolutely 150% over committed on work to catch up on, so likely it's buried in the hiring manager's inbox themselves.
If a question sounds like it's a deal breaker to you and the recruiter knows the answer is negative, you might not get a response (but you might).
You ABSOLUTELY should NOT jump over the chain of command and try to ask the hiring manager themselves rather than the recruiter. This demonstrates a serious lack of understanding of the process, and may give them the impression that you'll do this later by jumping over your own manager's head, which is an extreme issue that will ruin your career at the company (even if not getting you fired, typically it makes you that irritating pain in the butt to your manager from that point on). DO NOT DO THIS, avoid anything that may make you look that way, especially in the hiring process.