MCTMT New York Tax calculation question!

We applied the Tax configuration for the Metro Commuter Transportation Mobility TAX for New York State, USA.

BSI tubs 143 has been applied.

BSI support mentioned that

An Optional Rate Override is not necessary for the MTA tax. Once the bulletin has been applied, the rate of .34% will also be applied. Tax type is 19, tax wage type /419.

The question is, now /419 is calculated but I was told /719 should be equal to /703. Currently 401K differrals are exempt for this tax. Can you tell me if that is correct or not?

Thanks...