His name has never been confirmed as Enzo Monroe.Isn't it almost certain at this point that Zo (Enzo Monroe?) is Alexis and Layla's father? There have been many hints along the way, including Erynn not wanting him involved as he's "too famous" and a few other hints over the course of the game.
I also believe that Ximena is too young to be Val's Mom, wasn't it confirmed a while back that both Ximena and Gabi are 28?
There does seem to be a link there though, an aunt maybe?
He is still a major suspect of being their father, but not confirmed.
"Mr Monroe" might end up a red herring, the biological father of Layla/Alexis never appearing or dead.
Something to keep in mind is that Adriana uses Moore as a name, she doesn't the Monroe of her daughters or Navarro from Santiago.
Gabi is confirmed by Nyx as 28, people assume Ximena is the same age due to their friendship, plus some people on the discord(not Nyx) said she's the same age... i'm still waiting for some more solid confirmation.
The way Ximena plays the "big sister" of the friendship i can easily see her being a little older.
The often partially obscured model Nyx uses for Val's mom is 100% Ximena, she can try to play tricks here, but the logical thing would be to confirm Ximena.