People yank rock all the time. I just bought a football size rock with mushrooms on it the guy pulled from his display. The guy had no problem and didn't think anything of it. except needing to add water because of the drop in level in his sump. So just have water on hand to make up for the displacement. Your filtering system should already be able to handle the change.
I'm getting ready, been a week or more, to pull rock from my sump and go with Chaeto to see if there's any better results than the rock itself like I had on my old system. Besides my pod population is nothing because my fish. I have lots of rock in my display and only run a skimmer. Not expecting any real change and never do.
Now on the other hand and trying to sound more technical on the science part. In your rock maybe nutrients locked inside. So pulling it may even lower your nutrient level and adding the new water would be like a water change thus having no effect at all. True? I have no idea. I've been wingin it for 13 years and never had a tank crash.