I agree with you. This is a sweet little story. Sweet little stories rarely go viral unfortunately because I personally adore writing them and reading them.
To have any chance of a story gaining traction online you have to hit the opening hard. It's not like story telling in person where you ease into it kind of warming up your audience. Here they are going to bounce fast.
I'd take the paragraph starting, "My Dad had the WANDER gene. " and move it up to the beginning. Treat this more like a story not your memory and make your dad the main character.
Cut out all the parenthesis. If it is important enough it needs to be said work it into the main body else just leave it out.