I see the issue most likely which is not shown in his code above. The Text widget at the bottom of CreateUI() has probably been initialized and made somewhere only once. However in order for it to work you need a seperate widget for every player you are drawing the canvas for. That would look something like this:
I have this device controlling the main functions, and the UI is separate but the two interact. I think that having this device decide who to display the timer to, and the other device display based on this, should fix it.
Tested solo and it still worked properly, but will test with another later.
I can’t really see how you are creating the UI which is the part that is probably causing the main issue. If you want to display the UI for seperate people you will have to make seperate instance of the UI canvas/widget aswell.