BROONZY played a particular finger picking style which involved somme off the beat thumb bass, quite different from missippijohn hurt or mance lipscomb or piedmont style, it gives a bassy swing to the music, however my personal opinion is that blind blake played in a more jazzy chord style ,
however there are overlaps between different genres and to describe broonzy as jazzy is true to a certain extent, primarily because of hiss use of off the beat bass, however he did not improvise in the same way as true jazz guitarists like wes montgomery or django.
,DAVE GNOME i have no idea, you are very clever. i am sure you will find out on your own