Hey. It is still impossible to change the group member chevrons in any way (except for setting the transparency for all markers in the 3d world).
Instead of requesting the impossible, maybe the problem can be solved differently?
For example
ProvisionsTeamFormation shows an overlay with the relative position of all team members and when they die, their icon changes to a skull.
If that's not enough, someone could make an extension that allows to show a huge visible "go in that direction to rez" marker on the screen or maybe play a sound repeatedly until the healer lives again and the frequency of how often it plays increases with how close you get to his dead body.