Einstein was something of a scientific pantheist in his idea of how God is. I cannot see a relationship between any sort of pantheism and utilitarianism or the popular current version of it named consequentialism. Pantheism is a religious belief or idea about the nature or being of God, and utilitarianism is an ethical system useful to a limited extent in making choices for political policy notably.
Bentham and Mill were advocates of utilitarianism. It has nothing at all to do with one’s religious beliefs or even deontology following one’s religious ontology. Utilitarianism approximates what democratic governments generally might want to follow in pursuing the good of the people accentuated on the majority. One problem with it is the problem in defining or deciding what the good is in a particular circumstance; Plato’s republic had guardians making those choices for people as they were supposed to be smarter and better educated.
I am just not a pantheist, though I find the Harris-Yale approach regarding utilitarianism incorrect. I actually believe in God for a number of reasons, rather than the idea that matter in its solid state form in the Universe is God at all. There is a difference between God created everything and God is everything that involves protocols. Actually I am a Christian and also believe in original sin. In my opinion the fall and original sin are the problem of entropy and thermodynamics. Organic beings input energy- often eating other living things- that accounts for the original sin-nature of mankind- The devil tricked Eve into biting the fruit and the original sin got rolling. Human governance is different than utilitarian ethics. I like the approach of fixing particular problems commonly faced yet letting people run their own lives with security.