Flow calling parallel multi instance flow causes class error after random time

I have a flow with a parent/child relationship. The parent flow builds a collection that is used to call the child flow. This is called with a parallel multi instance. The child flow has the start set to Asynchronous Before and Exclusive. It will run, normally 10-15 at once and things run fine, then at some point, I begin getting instances of this error:

org.camunda.bpm.engine.ProcessEngineException: ENGINE-09008 Exception while instantiating class ‘com.data.project.delegate.RetrieveProperties’: ENGINE-09017 Cannot load class ‘com.data.project.delegate.RetrieveProperties’: com.data.project.delegate.RetrieveProperties

If I run the child flow manually with the proper data, this runs fine. Sometimes, it will run 100 correctly with no incident, sometimes it will run 1000 without incident, sometimes it will run 25 without incident. Also, this class is literally the first delegate that the child flow calls. Is there something that needs to be done to prevent this?