I think the PNWT is designed badly tbh. The distance between the top of the Micro showerhead slits and the air intake tube on mine is about 10mm... doesn't leave much room for error or tipping/using any way other than vertical once you've covered those slits with water.
If the splash guard had been higher, and the intake tube longer it would have avoided the leaks imo.
I have a similar inline water rig that has the holes much lower down and further away from the top of the intake tube, which is longer. The whole thing is a little longer than the PNWT, but's that's more to do with the mouthpiece (which I prefer) and the fact the 14mm female joint isn't recessed into the body. Can almost use it lying down
Edit: Wow, those pics came out big