Yeah you have the 1.8 bar twin pole sender, so it replaces the old white 1.8bar sender with a yellow wire. The yellow wire is then connected to the twin pole sender, to pin WK.
I don't think that sender is the right one for the gauge, buy you can always try it! You can compare the MFA reading to the gauge reading, if they're very different you got the wrong temp sender off the audi.