Just to be clear, the short-vol trade still has not capitulated. That flow is still active and very aggressive, as large footprints continue to show up as of yesterday and today.
To our knowledge, only two smaller desks have been carted off. The Vega rotated on the street over the last three trading days is still a blip compared to how much Vega was short going into the start of the month.
You don’t see VIX futures collapsing by 15 vol points in less than 48 hours if the short-vol trade has blown out. Such a collapse would occur much more gradually. What you are witnessing right now is a doubling down of positions, not the aftermath of a capitulation.

To get that type of Vega to shift lower, you need a larger, more aggressive flow to push it down.
Ask yourself, who do you know that runs a "yield strategy," and consider whether they are still around.
Most desks were able to meet the margin requirements by 12 p.m on Monday. because, by that point, the VIX was in the high 30s to low 40s.
Flow didn't puke up, it just hung around and survived.