[ziffusion]

I think it is important to remember that you are catching a person on their journey of acquiring and internalizing information. The reservoir of available information is almost limitless - so no one is going to come close to knowing it all. No point in testing for that. We all navigate the world on different trajectories through this network of information - so your milestones may not be the same as theirs. No point in confirming that theirs are the same as yours.

What you want to look for is their ability to process information, ability to internalize it, and their ability to bring it to bear in solving the problems they will be confronted with. You may have to do this with markers that don't necessarily match your own.

The richness of the network of information they have acquired so far is a marker. The nuances of the insights into that information they have acquired is a marker. The organization of this information into readily usable tools is a marker. These are what you should be looking for, rather than some preconceived ideas of what the markers need to be.