FWIW... I did email the address provided and didn't get a kickback or email doesn't exist message, I also didn't get a "we received your correspondence email" which tends to be the norm for automated mass addresses like this. Was your guys error message just from mailer daemon or what?
Its not like some people got emails and others didn't. No one received anything from receipt.application address. This fellowship hasn't been offered for a year, and I think they are still trying to figure out the process going forward and what it will look like.
Yeah its annoying that they didn't send out the email from NCER and that email address provided doesn't exist, but what can you do? I'd just take a nice big breath and relax. Worrying isn't going to increase your chances. Its the summer time and presumably you all like camping, hiking, and the outdoors. Go for a hike, take a weekend camping trip and don't check your email for a few days. Everything is going to be alright. All the applications will be reviewed, and we will hear back eventually.