It's actually more professional to avoid petty arguments.
There was a time I would care enough to respond to such "criticism" but those days have long passed.
Now I just write the facts.
Besides - if someone doesn't want to take advantage of the situation I could care less. I tried my best to help and that's all I can really do.
I genuinely tried my best too. I rather feel exhausted from trying too hard than feel guilt and regret that I was indifferent.