You have gone above and beyond, I can not say much more.
You have managed to get the site back up and running with a new server in under 24 hours, fantastic job from someone that runs this service on his own.
I just hope that the other miners think the same way, and that all the complaints stop and so on.
You realize he's not doing this for free right? He's making a ton of money - this is a business. There isn't anything wrong with reporting legitimate complaints.
Yes, I know this.
Here is the crunch, he did not know that NiceHash was going to be hacked, he did not expect the large influx of miners from NiceHash, so really the complaints are not warranted based on this, the server failed due to the extra work load.