The Rabbi said that it didn't matter.
The answer to her specific question was that it is more important why you bow, then when.
And then he said something that I really found valuable:
"If you leave the service a better person than you were when you walked in, then the prayers worked."
Powerful stuff. The whole point is not that you do it correctly, it's that you learn and grow as a human being, becoming wiser, more compassionate. No ritual can make that happen; it can only prepare you to allow it to happen.