You were very, very close to making it into the NGADM. This sounds like a really well-meaning audition that you've put together here. The singing is near-perfect, the harmonies are absolutely lovely, the timing is very precise... it would've been a pleasure to have an artist like you (and your acapella group as well) in the NGADM. Great work with this.
The reason this didn't make it was production-related. The reverb in here is too much. It's probably natural reverb from the recording environment (unless you purposefully added it afterwards), but it made the vocal layers sound considerably muddy. This sounds like a small problem but it was actually enough for you not to make the cut. Like I said, you were extremely close and in fact you're mentioned in the honourable mentions. Great job with this, shame we couldn't accept you through!