Every time I've called they have picked up right away. Sometimes when it comes to business you just need to shut down early and sometimes those days are unforeseen. As someone else stated shit happens. Had I been cutting it that close after them telling me they close at 5, I would have said I am on my way from xxxx and am running a little late. Will someone be there to help me with xxxx when I get there or can someone stick around should I show up 10 or so minutes after 5? Not making excuses for them but as a business owner I know first hand shit happens and sometimes you need to get out of dodge before the end of the day and if your an operation with very little staff it doesn't take much for this scenario to play out. It would have been unprofessional had you shown up and they were trying to get out and gave you the brush off or told you to go F yourself.
Not for nothing but your first post sounded like a legitimate venting session. Your follow up posts sounds like you are pandering to try and get a discount because of the situation since you are likely aware of their good nature of trying to get things right. I could be wrong but that is how it comes across to me.