The diversions were almost certainly for this reason. Crew scheduling, weight and balance, passenger manifests, flight plan filing with ATC for IFR, etc are all handled before takeoff, once it's in the air there's not much ground systems involvement required. But if all gates are occupied with outage impacted planes and space is tight or non-existent to stick more birds on location, have to drop it somewhere with room for dead birds. Could have also dropped it in a location with more anticipated crew availability when ops resumes, however much less likely given the outage ops likely didn't have a handle on that info or the ability to be planning ahead like that.
- Whether parent company has the capacity to service your plane at the landing location
- Whether parent company has the capacity to handle boarding new passengers for the next flight at landing location
- Whether parent company can get next flight off the ground from landing location
- "Risk" management by sending planes and passengers where parent company thinks it has better ability to recover to normal operations
- And probably a bunch more only people who work in that industry would think of