Well, seem like you just one of many owner of PPF who have the same problem here...
I hope my 5711 PPF, which are coming will be fine !
Follow my previous advice and secure it right away, it's not the first time a watch has a tiny little flaw, that once known, required only a quick fix when you get it to avoid future problem.
It's a shame for other people that lost the ball, but don't wait for that to happen would be my advice
How would one apply so little glue without messing around with glue?
Seriously, there is an "applying tool" or just to be careful?
This +1Cheap oil applicator could help, or simply the tip of toothpick