Also i do not see
it mentioned using vfio-bind shellscript to bind pci
device to be passed through to vfio driver. Also Roel
try booting with both emulated vga and passed-through
card. Maybe it will yield some results.
The setup in use is superior to vfio-bind, imo. That's
really an outdated script, there are better alternatives.
GeForce cards don't typically work as secondary graphics.
I agree with the suggestion to try a 4.1 kernel to rule
out absurdly slow boot scenarios.