Having seen the replays, I agree it was a 100% red card. I can also see why Dundee's 2nd goal was disallowed. At the very least, Robertson was distracting Ox. However, I suspect that it was for his movement towards Thompson. Had he been stationed out on a wing I would share Dundee's resentment.
I understand Tony Docherty's ire at the officiating but he failed to mention it in relation to Dundee's win over us earlier in the season. What goes around comes around.