a different way you can do is give the 5 items a trigger or collision action and a set bool value that will be set to true when collected
then on a different fsm you can use Countdown timer (this is a custom action and can be found on the
Ecosystem and put "bool all true" together with the timer
set bool variables to 5 and and the names you have given to your items
and check every frame on
in this way you can also check what items are still needed if you want to, but if you have many items it might be better to use add int on your items and use int compare like Richardh suggested
here are also several tutorial which can help you.
Friendly Greetings,
Dino