I have not read that DPC wants the game to end in BaDIK late spring. Where did you get this information?
Actually, BaDIK is a single flashback of the MC's past events. But I suppose you might mean that the MC in the last EP is an old man who, for example, tells his grandson how he met his grandma (LI), how the MC became the people his grandson knows. Then the last EP of BaDIK would actually consist of several comics (Branch accordingly) and the player reads the comic, what he has chosen himself by his own decisions. I thought of that 1-2 years ago and it would be a cool ending.
The nice thing about it would be that we could then see the college graduations, the MC marrying his LI, him becoming a father, and what career he has. I may be expecting too much.
I wrote a long time ago for Zoey to return and suspect for Zoey to be the backup girl for the MC when the MC screws up with the LIs. That was kind of confirmed in EP9. Zoey will definitely stay with us, I'm not so sure about Vinny. I think Vinny was only important to DPC for one thing, to give us a hint. OG DIK. Zoey is an "OTHER GIRL" and I believe that is how DPC let us decide Zoey's future role in EP8. If the player chose the "OTHERS" Branch in EP8, the MC can approach Zoey again, but there will be a hot battle for the MC's tail among the "OTHERS GIRLS". If the player chooses a LI Branch, he has decided that Zoey will remain just a good friend.
In the last paragraph you ask good questions again and you really do. But why don't you answer them. The clues are there.
"OTHER GIRLS" + ZOEY = DATES, RESTAURANTS, PARKS and BEACHES.
"LI" = RELATIONSHIP, ROMANTIC MOMENTS and FRIENDSHIP.