Just to be clear - if you are trying to amass enough proof to bring to the media, but expect to be fired any day now, the logical thing to do is to exfiltrate as much of what could be relevant and sort out the rest after.

Say you exfiltrate not enough and are fired. You're shit out of luck, and there is no way to infiltrate someone else to your position to get the rest out.

I doubt you can honestly see his actions as reckless or revengeful.