I guess how accurate is RC drilling to the depths of 2000'.. Can RC even get that deep? IMO JB want core drilling to maximize depth and info to sell project to a big player to delineate. With RC, they may still need coring to gather all geo info at accurate depths and locations.
I suppose if you think this is still at proof of concept stage than RC may be better, but I am guessing JB believes he has the goods and a few good core samples at depth will prove the geological theories and entice a big partner to step up..