Noc ult vs. Cait ult

Yes. It doesn't make him untargetable, just immune to CC.

Also, If noct got cait ulted...then ulted himself to an enemy away...would he get an unfortunate hard hit outta no where? x'D Like caits ult would just follow his ult and 360 no snope cross map snipe him. That would be highlight worthy

Yes be can block shots while ulting, He can also negate the damage all together with his spellshield.