Chiming in a bit late here, but I agree that your friends were quite callous in not sticking up more for you. It sounded like you were put in several uncomfortable positions that evening, thanks to their actions (or lack thereof).
It's good that (most of) your friends were apologetic. But if anything like this happens in future - eg, they change venues on you, at the last minute - I'd be inclined to simply go home, rather than go chasing all over town for them.
This is my feeling on the matter. Yes, it all worked out in the end. But, they were rude to you at several different points during the evening; they were unfriendly and unwelcoming, which is not how one ought to treat a friend regarding plans made in advance. If you're content with their apologies, that's great. But personally I wouldn't make plans with them again, at least not anything more complicated than walking a block to the coffee shop.
Think what they've shown you about themselves: they're unreliable and can't stick to plans that everyone has agreed on; when you go out of your way to be flexible with their changes, they won't go out of their way to be flexible for you
; when you ask for help and express concerns, they blow you off. I agree it seems like the sisters were the "active villains" here, but no one else stood up for you or insisted on helping you--someone could have offered to wait behind for you at the subway station, even if the sisters wanted to go on, for example. They just went along with what the dominant person/people wanted, at your expense.
Now, sure, this was just one incident, and maybe they'll learn from it. The one who apologized to you before you even said anything, for example--maybe that person has learned and won't act this way in the future. I would not automatically trust them again in a situation like this, though--they would have to earn back my trust that they'd lost that night.