It sounds like your daughter DID step up:
She arranged a sleepover party, and out of her control, things went south.
You read about a LOT of those on these boards (no RSVPs and a ton of people show, or YES RSVPs and either last minute cancellations, or no shows). It happens. It sucks, but it happens to most of us at least once.
How to make things better, without making things worse:
Consider how YOU would have felt if the situation was on the other foot: YOU arrange a party for your daughter, and it's not "good enough" for your mom.
First off, your daughter's probably hurting over this. She can't control what happened last year at dad's, she's broke and out of work and just finished up school, and the party didn't go as planned, and her mom is pissed off at her. HOPEFULLY she hid her hurt from her daughter. It sounds like she'd planned on having things be JUST FAMILY this year, and already bent over backwards to change things to suit your vision of how things should be so that you wouldn't march in and take over upstaging HER plans with a big party at your house.
So how to make it better.... Look at things from HER perspective, and consider what would make YOU feel awful or better.
Condemnations about how nothing is good enough & usurping her rights as mum/ anger at what already happened/ disapproval/ disappointment? Or .... ___________________?