The waypoints should show on any map card that is compatible with your Helix.When I mark a way point will it show on both cards when they are pulled up.
The waypoints are saved in the Helix unit, not on the map cards, so they show on any compatible map, including the Helix internal basemap.
If you have both map cards installed at the same time, only one map source will show on the screen.
You choose the map source.
Good luck