According to the IceColdCubano guy, the Jazz and Heat met this afternoon in Las Vegas. Allegedly, the Knicks are offering a package that includes Barrett, 5 picks and 2 swaps. The Heat are currently offering a package that includes Herro, 3 picks and 2 swaps. Heat may have the ability to potentially add one more pick. This guy maintains that the Jazz like Herro at least as much as they like Barrett. He also says that the Jazz have no interest to take back Ben Simmons, which makes a Mitchell trade to Brooklyn more difficult.
Take it with a grain of salt, but a package from NYK that includes Barrett, 5 picks and 2 swaps (if it's real) would be pretty tough for anyone to beat.