Thank goodness there were no serious injuries. I would feel the exact same way you are feeling. But I also believe it was a one-time thing. I was also thinking it was because you weren't there at the time. Maybe Mikey reacted that way to the other dog because he wasn't as comfortable without you there. Not saying Mikey started it, just saying I'd be curious to see if he reacted differently had you been in the area.

Please give Mikey some kisses on his adorable little face for me!