It’s good Dorico can be persuaded to make this notation. In general I want music software to be able to manage any notation that my pencil can.
I have some problems with the use of the tie here, though. These are the hidden corners of notational convention that interest me. After giving it a fair amount of thought, I don’t think a tie is the right notation for this situation.
As I see it, this tie is intended to show what the player does with one finger (leaving it down). On the face of it, it doesn’t seem to be unhelpful. But it also must mean (as with any tie) that the bow shouldn’t change direction, which is properly the meaning of a slur.
I am a cellist: I would certainly prefer to see a slur and not a tie, since I expect notation to describe the resulting sound first and foremost.
I would therefore abandon any attempt to have the notation describe the mechanics of fingering (ie tablature-like notation) and instead show a proper slur over the two notes.