That is totally bizarre. Sounds like he fears that he erred by disobeying the gedolim of his time in doing the activities he did. But his original argument STILL STANDS: "Lechi spoke about the eviction of the British from the land in order that Jews could make Aliya to Eretz Yisrael freely, and this spoke to us more than anything. The situation of the Jews in Europe pained our hearts greatly, and we felt we could help."
The real question is how could the gedolim have opposed it?
in my honest humble opinion, it is not Ravitz that needs to regret his disobeying the gedolim but the rest of world Jewry that must ask, why were those gedolim opposed to activities like Ravitz's that strove to help the situation of Europe's Jews?
(of course not all gedolim fit this simple mold, but of those that do, I believe this is the relevant question. Until it is answered, why should anyone who participated ever regret it?)