Definitely make sure all three lobes of your tool are aligned before use (it’s a little harder to tell with this style of bit) and apply even and adequate pressure to ensure it grabs as you spin the driver to prevent disfiguring the lobes/slot of the screw head.
Unfortunately my Y000 tool was perhaps not the best fit (tolerance a bit off) in these screws and I ended up stripping out the heads of all three of these. I started to panic but after I sanded the tip of my Y000 bit down a little with super fine grit (1000CW-C) sand paper to flatten the domed tip (visible with macro lens) and give it a bit more bite I was able to remove and reinstall without issue—in fact I had to remove and install them twice since I forgot my adhesive tape during reassembly, so the screws survived and the sanded bit worked.
One of my gaskets was as shown in your second photo, the other had been worked into the threads (as if smeared) probably from the factory and was completely unusable.
In place of replacements (unsure of where to purchase) I just used a clear silicone caulking on both screws upon reassembly to offer at least some water seal. I wish these gaskets were included with the gasket waterproofing sealant kit!