What's a good medical emergency you could fake and them suddenly feel better from once at a gate? In this case the crew probably wouldn't mind this little bit of "help".
But seriously, whether CO is liable due to their relationship with the regional remains to be seen, but the fact is that CO operations downtown (SOCC) does not control Express Jet, Express Jet ops controls Express Jet. Is SOCC, in addition to controlling every CO flight in the air at any given moment, supposed to also monitor every regional flight that they have a contract with as well?
And if they did know about it, what was CO supposed to do? That would be like saying that Express system ops would have any control over a mainline CO flight. Two separate operations.
Your main gripe is with Express Jet operations center.