The OP has thrown folk a little off course with the choice of topic title.
I read a post by John Barron on the Facebook Public Group page, in effect saying there is no integration (combining) of the apps planned.
So the key word is ‘inter-operability’, not integration.! The survey is trying to find out how the two stand-alone apps could work better alongside each other, to fulfill different needs/workflows.
A lot of folk would love to see some kind of ‘dynamic sync’ of transport/editing (which sounds a lot like ReWire - but I know the team have already dismissed that as a protocol they’d actively support). Don’t know if that’ll happen. I guess we’re certainly going to see some more flavours of ‘Export To…’, ‘Open With…’ or similar type options; the least I’m saying is, some enhanced file/project sharing workflow between the two…
Whatever, for me this is NOT about working towards some of Dorico’s Engraving options appearing in Cubase, nor Cubase’s MIDI editing tools inside Dorico, for example.