impossible, I wouldn't say that Burton is the ONLY influence on how people approach the vibraphone today. I'd say that Hutcherson and some of the others that you mentioned have been equally influential.
But I do agree with you that Burton's influence has been tremendous, and in some aspect greater than some of these others due to the fact that Burton's taught at Berklee for so long.
But the "only" influence?!?! I think that's a stretch. Think about it: Stefon Harris and Warren Wolf are probably the two most popular "younger" vibraphonists out there today, and they're both squarely in the Bags --> Hutcherson lineage.