How long does the puncture last?

Hi, I brought my cats to the vet yesterday to get microchipped. The Vet told me not to give them shower for a week for fear of the chip coming out. But my cats like to play rough. I need to fly them from my current location back to my hometown. What I am afraid of now is, when they are playing around, the chip can accidentally slip out from the puncture.

So, main questions are: how long does it take for that puncture to heal and is it possible for the chip to slip out while they are playing?

Thank you.