I Started a Gofundme Page for a Cause I Was Behind. the Money Raised Was Stated to Go Towards a Billboard to Raise Awareness.

Sounds like you are doing the right thing. When you take money from someone for a cause there is an expectation it will be used for that purpose. Again, it seems you did so just that. But unless you want to get involved in justifying how you spent the money, refunding it may be the simplest way to resolve the problem. We can be principled it practical, this is the practical solution. Of course you can always contact me for more answers.