I used Varathane when I was a kid, would buy it at Ernst and use it on furniture. I never thought it worked very good but it was the only thing I knew existed, I always thought it looked like a thick goop and not real professional. I haven't used Varathane in about 25 years so I'm sure it's changed since then. But if you're going to purchase stuff at Home Depot or Lowes then you better know exactly what you're looking for so you don't end up buying crap. Home Depot or Lowes will do their purchasing from anywhere regardless of quality, where as a specialized building supply store will take their time and select stuff that works.
But it sounds like your flooring guy didn't know how to read the directions on the label, drying time is listed on every paint, stain, and varnish. I know it's hard to find competent flooring guys that's why I usually do it myself. If I'm going to hire someone, I'm real particular, ask lots of questions, look at references, preferably someone I've used before. Have you tried calling the tech support to Varathane about the problem?