I experience the same thing
@Howie1968.
F.O. sights work very well for me out in the woods in low light (years and years of using F.O. bow sights to elk hunt), even under a pretty thick tree canopy, but when in a blind or under a roofed shooting area they just don't gather enough light to show up well.
I believe Brokennock's paint is worth a try, but you would have to "recharge" it on occasion. Certainly a risk of spooking off hogs to light up your blind with a flash light, but if it lasts for around an hour that isn't too bad.
Ever heard of tritium sights? They are mainly sold for unmentionable pistols, but perhaps a setup of those could be bought and then have a gunsmith drill and tap your favorite hog hunting rifle for them?