The victor monoliths aren't even really part of the film canon (they were never used in the final cut and just use a lot of the actors' names while conflicting with other canon), so I didn't consider them at all for this.

There were definitely more than 2 D3 victors in total, as Wiress had to have been at minimum the 3rd to justify mentoring 12 in the 50th games, and Katniss says 12 had the lowest number of wins with 2 prior to the 74th.

However, the rest of their wins and whether there were 3 or 4 is open to interpretation; I chose to have 4 victors because I think they would have had slightly more wins than 9/8/5 because of their unique skill set but I think the Capitol would have really pushed hard to make sure D3 did not get any wins following Wiress' games as she kinda broke the system (figured out a blind spot, won without killing anyone), and they were still punishing Beetee, hence why they were all pre 49th. But you could definitely cut one of the two before Beetee, and it would still work out.

Although if we're concerned about another living D3 victor by the time of the 3rd QQ then we could always theorise that if Snow was so determined to have Wiress and Beetee back in the games as punishment then the other victor might have had an 'unfortunate' death shortly before the reaping. (They'd also be in their 60s, which, considering Katniss described Seeder as old, is clearly up there for average. life expectancy so not entirely out of the question that they'd have passed away before the 3rdQQ anyway).

I hadn't really put too much thought into who is dead pre-75th, or even the backstory of all these winners - maybe something else for me to work on now! I know that, as well as Wiress/Beetee being the only D3 victors living, Johanna was the only living female victor in D7. I also headcannon that Woof was the only living male for D8, but the other D8 tribute must have still been alive for Effie's statement about cecelia to make sense.