Hydraulic lifters..... if the lifters are not oiled up, then they will tend to collapse with the regular spring pressures, and not push the valves as far as they will when running and pumped up. You're probably not in any trouble with that cam but be cautious with what you found this way.
BTW your piston height variations are darned good.
If I may ask, did you buy the rotating assembly already balanced by SCAT? I just don't see that being mentioned anywhere.