You'll note that I didn't actually assert the existence of the effect. I observed that a theory which predicts the effect the EmDrive appears to demonstrate, also predicts the fly-by anomaly, and offers a unified explanation for both.

Yes, it requires more confirmation. Much more. I'm not a scientist, but I think that, taken together, it's interesting enough — "Well, that's strange" enough — to warrant further investigation, instead of being all, "Meh. Measurement error."

Am I mistaken in that belief?

It's worth an investigation because it can be done cheaply and there might be something there. We've also investigated ESP and quite a few other weird things.

Unruh radiation is weird under some interpretations it can be used to reduce the inertial mass of objects, the thing I take from this is that I hope the EM drive could prove it rather than the other way around because then we might say we've discovered the "Mass Effect" ;)

It's also quite possible that the theory was derived to fit these observations. This theory has yet to predict anything new that has been proven. Until it does it only amounts to a possible way of connecting two unexplained and possibly flawed observations.