Oh come on! An attorney? Really?
We are encouraging someone to take a church to court?
Perhaps this person was a bit stubborn?
Perhaps they could have left the dog in a classroom, or the church hall, and their friend could have "led" them in to the church?
In a church filled with people, there had to be someone willing to extend an elbow to assist them.
Before looking for an attorney, how about contacting this eparchy's bishop, and see what he says. Perhaps he would allow it, or perhaps he could better explain why it's not permitted and suggest another way for this person to attend Liturgy without their dog in tow.
Getting the "law" involved in church affairs simply doesn't sit well with me. That should be a last resort, only if the hierarchs have for some reason failed to follow through, and if a criminal act had taken place.
....and if this person is ready to "leave" Orthodoxy simply because their dog was not allowed to enter the church, then they never really knew Orthodoxy.
How can you turn your back on Christ because your pet wasn't allowed to join you in church. Really?
What happened to loving God more than anything else? He that loveth father or mother more than me is not worthy of me: and he that loveth son or daughter more than me is not worthy of me. Matthew 10:37
I can only assume that he that loveth dog more than God is also not worthy of Him.