From the results so far, it seems we're following DMM's winners exactly. The DMM swan boat winners are listed in the Japanese DMM wiki here.

Winners:
[Prelim 2] Day 2: x30 Boat (First day for us)
[Prelim 3] Day 3: x50 Boat
[Prelim 4] Day 4: x10 Boat
[Prelim 5] Day 5: x100 Boat (Moon-viewing Bug)
[Special 1] Day 6: x20 Boat
[1st Half Final] Day 7: x30 Boat

[Prelim 6] Day 8: x10 Boat
[Prelim 7] Day 9: x50 Boat
[Prelim 8] Day 10: x30 Boat
[Prelim 9] Day 11: x20 Boat
[Prelim 10] Day 12: x50 Boat
[Special 2] Day 13: x100 Boat
[2nd Half Final] Day 14: x30 Boat

[Exhibition] Day 14: x10 Boat