This exact thing happened to me - at the Mayo Clinic, of all places.

I found the same info after the initial test, then refrained from lifting for a week before the follow up lab work. Tests were normal the second time but had they not been, I'd have been given a (presumably more expensive) ultrasound.

My only guess is that the lifting-bad-liver-panel effect isn't something that happens often, since so many people strength train these days.