Yes it does come from Basi Legani. I see you conferred with someone to check that out. (Half an hour ago, my comment was chinese to you. Now you know the sicha by name!) If the Chanadniks don’t interepret it that way, then how do they interepret it? And why was it taken out of later editions?
You may be aware that it is this very quote that triggered the Brisker Rav’s famous line of, “Ehr redt zich ein az ehr is Moshiach.” The rav passed away in 1959. So the biggest gedolim caught on a lot faster than the hamon am.
No one thinks that he thought he was Moshiach back in the Sorbonne or wherever he was in the past. That he didn’t accept in the beginning doesn’t prevent it from becoming the philosophy when it happens late. Only that the mantle of leadership grew very quickly on him and fit quite nicely once it was accepted.