Looks like you are from Texas. Glad the vinegar solutions work for you. Up here in the high desert of Nevada we have weeds that vinegar, salt and even roundup will do nothing to, in fact I think roundup just makes them mature and throw seeds. It is a chore to keep up hand weeding in our small garden.
The nuclear underground tests are most certainly responsible for such tenacious weeds
Maybe some real water would work? Or distilled?
I also use a flame when there is not a burn ban. That works well too. There’s also the old fashioned method of getting down on your knees and pulling weeds by hand. That only works in a small garden like mine (2400 sq ft.)