After digging through your project I was able to find that you are not setting the initial value for the “Desired node” for the other actors that are being spawned in. Also, the fact that begin play is used for the initial value was casing issues. I set up a custom event to fire off on spawn. I have provided a screen shot of the changes I made to help clarify. I hope that this information helps.
Example:
Make it a great day