Hi guys,
from what I have found in my talking to a lot of people in the past 12 years of my Krav Maga "career", the answer to the question "Who is the highest ranking Krav Maga Master?" is not that simple.
As long as Imi was alive, everyone refered to him as the highest authority of Krav Maga.
In the last few years of his life Imi was very ill and it was in that time that the "Krav Maga Association" started breaking apart. (Eli Avikazar (RIP) had formed an own organisation before that time).
The reasons for the breakup and breakaway of various instructors varies by who you speak to, but I believe "big egos", politics and diverging opinions on the direction that Krav Maga should take played a key role. Possibly the lack of strong leadership from Imi in those years was also a factor.
Haim Gidon held the KMA together (later IKMA). Haim Zut formed the KMF. Eyal Yanilow formed the IKMF a couple of years later with other senior instructors.
So who is the most "senior"? Well, in age, Haim Zut definitely wins.
As for the "legitimate successor of Imi", I don't believe there can be one. Imi obviously didn't lay claim to the term Krav Maga and openly welcomed many Krav Maga instructors in his last years.
Photos from the years 1996/1997 show an Imi marked by illness, posing with lots of different instructors.
Personally, I would be very sceptical about any "written documents" that are in circulation from those years. As one senior instructor once told me, he was heartbroken when he met with Imi in 1996 and saw the feeble medical state he was in. Anybody could have asked for an autograph from Imi and he would have signed anything (and a few unsavoury characters did get signatures from him on dodgy documents...).
Anyway, I believe it is pointless asking who the highest KM master around is.
Haim Gidon, Eyal Yanilov and Haim Zut and their respective organisations are good bets if you are interested in training Krav Maga.
If you have the chance to take a seminar with any of the three, they will also most likely be worth their money.
If you have the luxury of having the choice of several schools in your vicinity, test them all and stay at the one you feel most comfortable and that suits what you are seeking most and that makes most sense to you.
Personally, I have trained with Eyal Yanilov many a time and believe him to be an exceptional instructor. If I ever have the chance to train with either of the other two named above, I will make an effort to be there.
Regards
John