Generally speaking yes, though its probable that the necessary genes could be present in certain other landraces recessively.
Also, Walkabout is a random mix of extra seeds and possibly test crosses. Nevil crossed Ruderalis to a few chemovars back in the day. It's always possible that Shanti popped old beans of Nevils to test and or cross. If that's the case, that walkabout pheno could be very rare. No way to know though.
Or, maybe she was simply an anomoly.
Either way, it was a fun grow to watch she sounds delightful. @Skuncle Lenny thanks again for sharing her with us.
I believe Diesel is correct here.
The "auto" or ruderalis trait is recessive. So this would mean that say 1 or 2 seeds out of a batch of 5000 seeds of any line can exhibit "auto flowers".
Making those finds quite a rarity.. the hungarian ruderalis originally used would have been most handy in stabilising that gene quickly (still at least 2 gens breeding in most cases to stabilise).. as finding recessive females AND males in a single seed line to interbreed would require some serious numbers popped... And/Or serious luck.