yup this works, fill your whip canister with cold brew then charge it with a cartridge, throw that cartridge away then put a new charger on the canister and KEEP IT ON (this is needed to maintain pressure). Then your ready to go! Just turn upside down and dispense like you would whip!

I think so, I think I heard about someone doing that at home or at a small restaurant

Excuse me? Never heard of this. I know you can do cold brew whipped cream but not nitro

It wouldn’t be Nitro coffee unless you used Nitrogen chargers. The standard whipped cream chargers use Nitrous, a different gas. Either was the result is usually off compared to keg quality.