Wrong PhD better than no PhD?
I don't know what is right for you, but I'll tell you that there is little in life that is worse than a career in something that you don't care about while having unfulfilled dreams.
I suspect that you are early enough in your studies that a change won't cost you much, and spending a year now to avoid 30 years of boredom might (might) be a good investment.
There are a lot of people in the world who don't get a chance to choose. If you do, then, perhaps you should look for an optimal path and see if you have a way to follow it.
Changing fields after a doctorate is not impossible, but hard since you need to perform in the old field while preparing for the new. That takes time also.
I can't answer the specific question about balancing MS degrees and such since I don't know your goals for a &quot;job&quot;.

Your life isn't a &quot;dress rehearsal&quot; for something else.