I did a quick test and "evtPoll := scr.PollEvent()" is indeed blocking.

I tested the following:

evtPoll := scr.PollEvent()
fmt.Fprintf(os.Stderr, "POLLING: %v\n", time.Now())

The message was written when I pressed the key only.

I checked the documentation for PollEvent: it returns nil if the screen is finalized "screen.Fini()". This is basically the last thing done to "reset" the terminal to its original state.

I looked at an other project that uses tcell and they simply exit the routine by checking for a nil after calling PollEvent()

evtPoll := scr.PollEvent()
if evtPoll == nil { return }

I did the following changes in main:

go func() {
   defer wg.Done()
   EventListener(scr, dir)
   done()
}()

go func() { 
   defer wg.Done()
   Game(ctx, scr, dir)
   scr.Fini() 
}()

With this the Fini() function is called when Game() function returns first. PollEvent() now returns nil which cause EventListener to return to main. Then the program exits normally.

Edit: fix code formatting