I'm not familiar with the layout of the Alhambra but I'd first look under the scuttle panel, you might want to take off the windscreen wipers to get easy access. You might have the cabin filter housing there in fornt of the passenger position and that can be a source of water ingress. Also check the drainage holes, they can get clogged which will back up the water forcing it to find other ways out.
On the other side in front of the drivers position you might as well check the wiring loom passage into the cabin, but that would not let water go into the passenger side.