Flex and flock have their limitations. You could not get the look of your 'You Can Change' design with them. Same with 'Be the Change'. Flex and flock is material cut our of a platic sheet, then heat pressed on to your garment. The cutter can't do anything smaller than .06 wide.
Your wallpaper completely renders your explanation of digital transfers unreadable
Vuew . You should change your text to white. So I am not sure if this is their direct-to-garment print method? If not, you can try that method and see if it looks any better.
If you decide to try flex/flock, Photoshop is not a native vector program. Illustrator would be easier to use, although I think you can export an eps from Photoshop?