It would be jumping off the shark if he was Alexis/Layla's dad, when Emily was pregnant, Alexis was already a 2 year old and Adrianna was either already pregnant again or would be shortly.
The couple Adrianna and "Mr Monroe"(who seems to be a good father to both his daughters) is still going to this day, probably not something that would happen if he was messing around with her roomate while in a relationship with her.
Then again maybe he ducked going to the restaurant upon learning it was owned by Emily(just playing devils advocate lol).
There are hints about him from both of his daughters(makes it difficult to get all hints in a single playthrough)
When you train with Layla at the park she speaks a little about her father, that he was a basketball player.
Alexis on her path says they can't use her father as the guy who "hires" Erynn to trick Ethan because he is famous.
So i suspect their father is Zo, retired basketball player who the MC was a fan growing up.
Zo and Santiago are not the same person, they were friends in college, Zo is off-screen (he's always off screen or shot from his back) in that flashback where Santiago gets rejected by Emily.
The question has always been is the MCs father Navarro, aka the sports agent?
The name Navarro can easily be his surname and his full name Santiago Navarro.
Having a talented basketball prospect as a friend might've given Santiago a good route into being a sports agent, that familiar story of "started working with this one guy, later expanded" kind of deal.
Navarro (wether he is Santiago or not) is married to Gabi, it explains her being pissed off that he didn't stop to say hello in training camp, she also has a "he looks like him" thought bubble when she first hooks up with the MC.
They also have pictures together dating back to when Gabi was a highschooler(good going Navarro
).
Solid point as well.
