I should clarify my position on this issue. I do not condone workplace violence. I expect to come to work and not have to worry that I may have to physically defend myself against a supervisor.
That being said, I think the 2 day suspension is appropriate. The push, while inexcusable, was certainly not enough for this person to lose their job, let alone get the local authorities involved or warrant the issuing of an order of protection.
If this were me, I would have requested a meeting with the center manager, the supervisor, myself, shop steward and/or BA upon the sup's return from his suspension. I would have outlined my concerns and insisted upon a guarantee that this would never happen again. Finally, I would have requested and accepted an apology from the sup. I would hope that we would then shake hands and move on.