Balance-shaft-timing belt has teeth & runs on sprockets like the camshaft-timing belt. So it won't really slip like a friction belt.

But it DOES have it's own tensioner pulley which can have a noisy bearing.

 

doesn't sound like a bearing noise... like nba players screeching thier fresh sneaks on the smooth hardwood floor. Does the belt rotate against the tensioner? I'm thinking its probably making noise from that.... But it shouldn't be a big deal if I just leave it alone?

 

The tensioner pulley has no teeth & it rides on the outside smooth surface of the toothed belt. It hasvery little momentum & it doesn't extract power for anything,so the only way it'll screetch is if it's bearing is beginning to seize. Same for the balancer belt.

Bearings can make all sorts of funny noises when they fail. So the nature of the sound doesn't really prove it. If the tensioner pulley is squeaking against the belt I imagine there would be some visibleevidence on the outside of the belt (take off the upper timing cover).

If it's the timing belt tensioner, it's only gonna get worse & burn up the belt. Then you'll discover what it sounds like when pistons hit the valves.

You can completely remove the external drive belts & run the engine to rule them out as a source of noise. Until you do that, I'm gonna keep my suspicion that the noise is outside somewhere.