there is actually. All he'd have to do is rotate the crank and he could get the big end of the rod and even mic the journal. I've replaced a full set of rod bearings in an engine without any issue at all. Takes time like anything else but is def doable.
I cringe when I see ppl use plastigage...while I know its a "general" oil clearance method and would suffice in a time like this, I'd still try my best in obtaining a true measurement