If there is only one bubble for each bad guy, add these objects to a container.
You will not need to link them by ID or UID, when you pick the guy instance in events, its own bubble will be picked automatically.
For each Guy -> Bubble set position to Guy.x, Guy.Y
Guy on collision with Player -> Bubble flash for 1 seconds
When you create a guy, its bubble will be created automatically.
When you destroy a guy, its bubble will be destroyed automatically.