After getting some feedback that some things were not working on the exported builds on other computers, I looked into the problem and found that it was a navigation error. I'm using Godot and had the location of the cards housed in "res://" and that tends to go wonky with things. After finding a new plugin called Godot Resource Groups, I rewrote the base code entirely. And around GRG and got it working with fewer lines. I now just need to fix the stuttering of the shuffle before the cards flip over.