Hi. Even though your poweer steering fluid is up doesn't mean your pump isn't making noise. But I would doubt that is the problem anyway. Problems with steering pumps generally make themselves evident at lower speeds or while negotiating steering maneuvers like parking. Did you accidentally hit the winter driving button? I've done that a few times on mine, but I didn't notice any unusual sounds. I don't know if it could, but that might possibly evoke noises from a tranny at highway speeds for if left on for long periods.
Have you checked the Trans fluid again since the change? Assuming they added the correct amount, is it still over the mark and bubbly? Not sure if I'd be too concerned if it was a little over with a few bubbles in it after a 20 minute or so drive. Especially if there are no shifting problems associated with it.
Perhaps it could be a wheel bearing (hub) starting to go. This would tend to get louder and more noticeable. The curious thing there would be that, again, it would more likely be noticed at lower speeds when there is less ambient noise and then at higher speeds as it gets worse. Not generally the other way around. If it is a hub, and it gets louder, it should be checked promptly.

The belt tensioner actually might be a good guess. Earlier models absolutely had issues with the pulley. I think they straightened that out by 02, but I think 105K is due date for a timing belt on an 02 which means anytime from about 90K on would be a good time to replace it. I don't know what the recommendation is regarding the pulley on the 02s, but I would guess it would be replaced with the belt. Get it checked. If it is the pulley, tensioner or even the water pump, it should be fixed immediately. If the belt fails, the engine will be damaged, likely ruined. If the diagnosis for the noise is inconclusive regarding the timing belt/pulley, I would be inclined to get it done anyway with the car at 90K.
Sorry for rambling, and I couldn't be more help. Maybe someone else with more expertise will ring in. Good luck with it