Even though it not clear that the Gel layer of memory foam in the Zinus mattress let the heat escape or not, but it surely is able to resist body heat so that the person can sleep cool all night. Further, its cover also has the ability to keep you cool at night.
On the other hand, the sink age in the comfort layer of Tuft and Needle Mint mattress could lead to some overheating, but the company has infused this layer with graphite which helps is absorbing and dissipating the heat as you sleep through the night.
This means that both of these mattresses are good at regulating temperature, regardless of how they do it.