If you peer into the tray slot in the printer, you’ll see the front feed rollers. The top ones have teeth. In my Canon, these front rollers have a gap between them about the thickness of the disc tray. So they act more as guide rollers, and don’t really grip the disc at all, just the tray. On the Epson, they have no gap, so the tray forces them open. If the disc is thick enough, they will contact the disc.
This issue could be more to do with the adjustment of these rollers in a specific printer, more so than in a model line itself. Beats me, but it’s possible that one will do it and another will not, even in the same model line.
Watershield discs are thicker, but are also a softer surface.
I wonder if you attached a piece of heavy paper to the top of the disc tray, if it might open those rollers enough to avoid this. In other words, make the tray thicker.