I hope that the "couple" forgave he/she for not having ice and having to make their room up one day after 1pm. I am sure they were out of the cabin in time for them to make it up, and they did not come in between the morning and night service and find melted ice as the reason this person lost their income.
I tip according to service also, but part of that is understanding how things work. I don't understand how the service got worse. They make your bed and clean your bathroom.
If no one showed up to do these things, they should have called the Information Desk. It does happen I hear. Has never happened to me.
I know my Steward's schedule, and He knows mine. He/She always have worked and been there for me.
Have had not so great Stewards. But have never stiffed them for the service they did provide.