Have you spent any time looking for answers? Wikipedia suggests Theia started on a similar orbit to proto-Earth. [0] In that case, a collision would have left the combined object on a similar orbit to both initial bodies. I actually didn't know this before, but found it in about 3 clicks from googling "theia impact earth orbit". I can't find a really handy source for it, but I also know from various sources that gravitational interactions among the objects in the solar system tend to reduce eccentricities of each others' orbits over time. The best I can find is [1], which probably did play a role even if it's not exactly what I'm thinking of.
Nothing you posted answers the very basic question I had. Even the Wikipedia article says that the hypothesis doesn’t have any real answers because of all the inconsistencies.
Let me give you a pro life tip. When someone comes up with an extraordinarily complicated scenario or hypothesis and it can’t answer a very simple straightforward question, it most certainly means that the the hypothesis is wrong.
It answers your question pretty comprehensively, actually. Not my fault if you can't connect the dots.
Sure, there are still questions. But the questions for all the other explanations of the Moon's origin at even bigger. You can be skeptical, but until you have a better theory that accounts for all the evidence, you don't get to dismiss it as "science fiction". Not if you want to be taken seriously anyway.
Here's a life pro tip: The correct guideline for a theory is "as simple as possible and no simpler. The real world is complicated. Complicated things happen all the time.
[0] https://en.wikipedia.org/wiki/Giant-impact_hypothesis#Possib...
[1] https://en.wikipedia.org/wiki/Tidal_circularization