custom depth overlapping

hi everybody here. i have a custom highlight (altered survivor vision from marketplace ) function using custom depth and i use the marketplace asset waterstamps, for waterdecals on transparent objects. the waterstamps look fine, but they are overlapping the highlight function of my interactive objects. i have no idea to stop this behaviour. i tried setting them to different custom depth layers, but they still overlap.
Does anybody have an idea ? kind regards stucki