Even in the walkback, Mulvaney does not say there was no quid pro quo. He says unblocking military aid was not conditioned on DNC server 
he does not say was not conditioned on other investigations into Burisma, for instance. the one he now denies is the one DOJ fears link to
(I recognize this is parsing from a planet where words still have meaning, unlike the WH’s). but point is, DOJ may have wanted to distance
the Barr/Durham investigation into origins of the Russia probe, which may or may not involve the DNC server, from the withheld mil aid
see this
