I previously had a question on using AC reference voltage with MDAC, But it has been addressed nicely in below post

[https://electronics.stackexchange.com/questions/702254/how-does-the-multiplying-bandwidth-specification-relate-to-a-dac-outputs-maxi/702256#702256][1]

But How would the fluctuating reference voltage not impact the output value, considering that precise DC Vref is not required?