Well, that depends on what the sound is. Typical single cam idlers have bearings in them on most bows. This sound could be coming from that bearing. I would have a shop pull the axles out and check the bearing and the other end as well. If the bearing is wore out, all the lube in the world isn't going to fix it. Also, taking it apart allows you to thoroughly clean everything and lube it up before putting it back together, which is preferred.

As far as rem oil. I'm not sure, but I don't think it will hurt. As long as its not a penetrating oil like WD-40 or similar. Personally, I use a good pure teflon spray when I have to do an lubricating of things. It dries well and leaves no messy residue like oil would, which in turn will collect dirt and dust.

Hope this helps