Vardon was almost unbeatable at the height of his powers, but had two bouts of tuberculosis that saw him unable to play for extended periods. In later life he also developed a "flinch" on his short putts; likely what we now call the yips. He remained a wonderful ballstriker all his days.
Vardon is most famous now adays for having given us his over-lapping grip. It remains the standard for most good players to this day. One thing that Vardon said about his grip that I think is vital for all golfers is that the knuckles of his left hand should face the target line and the knuckles of his right hand should face exactly the other way. In other words, the palms of his hands faced eachother and the back of his left hand and the palm of his right hand faced the target line.
When wanting to figure out how to best grip the club, Harvey Penick suggested we grip a ruler, or a yardstick, as though we were going to use it to strike a ball. Most if us would naturally grip the yardstick with our palms flat against the flat surface of the ruler. If we then were to prepare to hit a ball, our right palm would face the target line, and the knuckles of our left hand would as well.
If you have an uncomfortable grip, try the yardstick idea. Then place your hands on the club the same way. If you don't have better results gripping the club this way; whether you overlap or interlock your fingers, or just use all ten; I'll eat my hat.