You cannot as we are all other users here and volunteers who may or may not check these forums on a regular basis - we do not have regular hours as we do not work for Apple. As well, these are international forums, so for some, it may be in the middle of the night.
If there are no answers it usually means that no one has an answer or idea for you. Unfortunately, that can happen, especially since this is not a technical support site staffed with Apple employees/tech support. If you bump up your own thread once and still do not get an answer, I'd recommend booking an appointment at your nearest Genius Bar (the advice/troubleshooting is free).
As for calling something to someone's attention by posting in another thread is generally considered bad form as you are, in essence, "threadjacking". Every person posing a question deserves their own thread/discussion without, what would be for them, off topic and irrelevant (to them) discussion amongst others (unless it is absolutely critical). Once you attain enough points, you can do so in the special forum which is reserved for people with 8,000+ points - that is where we post a "bat call" for someone else to step in.