Integration is the process of assembling or otherwise combining the separate subsystems into your final overall system.
Testing involves making sure your components, subsystems, and overall system meet their tolerances and perform as expected. This is typically done all along the integration process.
The majority of CubeSat launches take place as rideshares, that is, they hitch a ride on a rocket purchased for some other, primary, customer.
What I'm interested in is the influence the primary payload on the launch has on the standards to which hitchhikers are held. For instance, can a very risk-averse primary disallow CubeSats with propulsion? Does a CubeSat operator need permission from the primary operator to, say, turn on its radios? Do some requirements get relaxed somewhat if the CubeSat is housed in a container, like the P-POD?
Or, does the primary have no influence at all, in which case the CubeSats need only meet the requirements set by the launch vehicle provider?
Essentially, how closely do the CubeSat folks work with the primary payload folks?