Hi maximizedmom77,
That’s a little thicker and lower density than the “no more than about an inch or so” of lower quality/density materials that I would normally suggest in the guidelines here.
Once there is about 2" or more of lower quality/density (less than 1.8 lb density in a one sided mattress) and less durable materials or “unknown” materials in the upper layers of a mattress then the odds of more rapid foam softening and breakdown that can result in the premature loss of comfort and/or support would be higher and foam softening and the loss of comfort and support isn’t covered by mattress warranties (see post #174 here).
Phoenix