They said they are aware of it and are looking into it. I believe I saw a few comments from as early as January saying they also got that e-mail from CDProjekt about this quest. When they went to fix Takemura's call bug, they apparently didn't look into a global fix that would overhaul the coding of quest triggers, but instead only focused on the one that was literally necessary to finish the game while ignoring other important side quests. Quests not triggering due to a call bug with commonalities with a quest they already have bug fixed shouldn't exist anymore after nearly a year of the game being released.
Those quests are not required to trigger Ex-Factor. I went back to an earlier save from just before I finished "Both Sides, Now," finished that quest, got the text about Eve's burial, then drove around and eventually got the call from Judy for "Ex-Factor." As I said before, that save was before I started M'ap Tann Pèlen and I Walk the Line. I think Ex-Factor isn't triggering possibly due to the text about Eve's burial being bugged and not arriving on some people's playthroughs. That could be a dependency for triggering Ex-Factor.
So I've provided proof it has nothing to do with finishing "M'ap Tann Pèlen" and "I Walk the Line." If CDProjekt wants to share that there is something else we need to do in game, they would say so instead of saying they're aware of the problem in the responses they give to people.