The
mapy.cz app seems to be good at showing the major variants, and the GR 654 seems to diverge from the Vézelay Way proper quite significantly. And there's both a Via Lemovicensis trail and a different Voie de Vézelay one -- though they frequently converge with each other into a single trail, and with the GR too sometimes.
In spots, all three diverge anyway from what the historic route should be -- sometimes sensibly, just to take a better walking route than the tarmac, but at other times the routes do not pass through the villages/parishes but go around them -- which is a frequent annoyance on modern French hiking routes constructed around the old pilgrimage Ways. Still, it seems you already have a handle on how to deal with that.
I walked the Mont-de-Marsan > SJPP section of it on my 1994 from Paris, and at the time none of these things existed, but with some minor exceptions the waymarked route there follows the DIY route I found for myself.
It seems fairly messy between Limoges and Périgueux, one of the options even avoids Limoges entirely which seems crazy to me from any traditional perspective. And between Vézelay and Limoges you may find yourself choosing between routes and DIY on a day-to-day basis.
After Périgueux things seem to get a bit crazy, with some major divergences -- indeed one of the options seems to lead to the Le Puy route at Montréal !! IMO you'd really want to go downriver from Périgueux to Mussidan, then carry on from there via La Réole and so on.
Anyway, mapy.cz does seem to be pretty good for this route and its multiple variants.