I wasn't certain about his heart center for a while but a few days ago i watched some videos of his, and i'm very certain on the 4 now.
as for core 6 or 1, i can see both as possible, i leaned more towards the 6 because he's so 'heady', but as in the case of many people, it seems two centers can play out almost equally.. i can see that clearly in myself for example, being both 4 and 5 equally.
it would be interesting to compare how his 1ish patterns differ as an FeNi from say.. TeNi ben shapiro's 1ishness..