I have been reviewing several studies online, and the general consensus is that MRKH IS hereditary, but not in the normal sense of "parent-to-child". Instead, it is a genetic fault that can remain partially in the DNA, dormant for years. And suddenly, through the chance combination of more DNA during conception, these genes become activated. So just because I have MRKH does not necessarily mean my children will directly inherit the syndrome, even if we go with a gestational surrogate for the procedure.
There is also speculation that it is just a freak accident during development, but that does not explain how a mother and daughter do not have the syndrome, but there have been cases of an aunt and a niece both having the same syndrome. I have not heard of any cases in my family of women having MRKH, but that does not mean it doesn't exist.