Hi Janieky,
That would depend on the density of the quilting foam.
As you can see in the guidelines here … once you are at about 2" or more of unknown foam in the upper layers of a mattress then it’s important to find out the density of the foam layers to make sure there are no weak links. While it’s not generally a weak link and it’s almost certainly fine … I would also want to know the density of the foam in the base layer.
Phoenix