A 17C ferment is probably a little low for that strain, so I'm not surprised it is peculiar. Sounds quite sulphrous which is to be expected with this style and strain, perhaps just OTT in this case. It may fade but Wits don't generally keep that long though, so you'll probably find it is perfect when the very last glass is poured and then the keg blows.
You may also find leaving it in the fermenter on the yeast cake a little longer can clean up some of the undesirable character, eg. as per
acedaldehyde. I am now particularly lazy and lethargic when it comes to most ferment schedules, a fortnight minimum in primary, only move it well after stable FG is reached and I feel it has helped- never rush this stage of brewing.
You may be able to scrub some of that aromatic character through a few CO2 purges although now the keg is carbonated that could be a challenge I.e. if using ball lock kegs, remove beer out QD, GENTLY place the gas in QD on beer out post, use just enough force to discharge gas into the keg through the dip tube, vent headspace through central relief valve- repeat several times. YMMV with this technique but could be worth a try if you are patient; don't blame me though if your QDs don't appreciate it.
If you really want to know what a farty Wit is like, try Wyeast Forbidden Fruit 3463, the stench is horrendous throughout the ferment but from the results its worth every bit of the discomfort. I used to use 3944 but have now switched to 3463, its still a refreshing, sprightly and delicious character, but yields much thicker and richer flavours when handled correctly.
Hope that helps! :icon_cheers: