Please let us know what the results are.

I hope you get miles refunded for the fare difference and a bigger travel voucher for the trouble.
Does Delta ever solicit for volunteers to downgrade?

He/she has a point. Think about who you wrote to. These are real people sitting at a computer reading mostly complaints. They know what it looks like when someone gets hosed. They want to help and they like knowing that they made a bad situation at least a little better. But when a complaint strays from the root of the issue, then the person reading the complaint might just chuckle a little and not consider it as seriously. They could be thinking "wow, that really sucked for his/her parents. They deserve more... Oh, wait, he/she's just complaining about delays and other stuff instead. We don't have much control over those things..."

I think it's the same way with any industry or situation. When you have a complaint, the best way to be compensated is to stick to the facts and be concise, not straying off-topic at all.