Kubo covered his tracks very well with this weeks chapter, so I don't understand exactly what major detail your looking for in the connection between Masaki and Yhwach. Fact is, even if Masaki wasn't directly part of the Vandenreich, she still came from a pure-blood Quincy background, plus Yhwach is indirectly connected to "all" Quincies just by blood alone. To them, he is the King, God or whatever and Kubo has yet to reveal more information about him and his own background.
For all we know, Masaki's mystery family background could be connected to Yhwach for all we know. But, either way, the chapter cleared everything up and anything else you want explained, you'll have to wait for Kubo to reveal.
^I don't see how "release" can mean "infuse".
Why do most of you call juhabach by the name Yhwach now? I saw where he was called Yhwach one time in the manga, but I don't get the significance of having two names...