Leaving the partner thing asie (as we don't actually know what that means) and taking a step back, it does not make sense that full unfolding only happens via locally stored files. Very few vendors make MQA available - I have found only 6 albums worthy of purchase. And truth be told, outside of Japan, there can't be more than a few hundred albums available in MQA. So my thinking is, MQA must surely be accessible via USB - otherwise, what would be the point - unless there was about to be an explosion of MQA availability as an alternative to normal wav/flac/DSD...
<EDIT>and curiously, Sony is not listed on the page you referenced under DACs providing full decoding capabilities. The plot thickens.....
</EDIT>