Text in RDX and MDX
 

We own a 2017 RDX Advanced and a 2015 MDX Tech.
We have Android cell phones with Verizon.
My wife can receive text messages in the MDX, but not the RDX.

I can receive text in the RDX but not the MDX.
For clarification my wife drives the RDX and her cell is an Galaxy S 7 Edge.
I drive the MDX and my cell is a Galaxy S5.
Yes, Text is enabled in both cars.

Try deleting all phones from both cars and all cars from all phones and then pair only the ones that are really needed - S7 in the RDX and S5 in the MDX.

Only those 2 cells are on each car.

You need to remove them both from each car. Then add only one phone to each car. See if that works.