Well, what I did days ago was take some RV grade black silicon (had it already from past outside window seal patches) and filled in the two holes in the frame that was leading to a sloping grade inside on the window frame.
I have NO idea why they were there... why would you want the water to drain INTO the van? Maybe it had plastic weep hole covers like I have seen for sale
online for Hehr windows, which these may be. Anyhow, I covered the 2 small holes in the silicon and now there is no leaking. There are still drain holes facing down on the OUTSIDE of the window which does make sense.
While it doesn't seal the window itself from heating/cooling loss, it needs the new seals for that, it does stop water from coming in which was most important.
I also sent an email to Hehr with photos and asking if they can identify the window model, if it's one of their old products and about the seal itself.