These are the facts from the game, to be (I would have though) fairly easily utilized to deduce who Sage's dad is:
- Sage says her dad has shown up to the party
- He expects his daughter to be there but can't find her
- Sage says she's avoiding her dad.
- He has red hair
- Sage has red hair
- red hair is hereditary thing
- Sage says her dad is there looking for business opportunities and kissing asses
- He is there schmoozing people and even lists all the people he needs to see: "I still have to chat with Dr. Johnson, Will Burr, Sir Gregory and Professor Burke..."
Quotes from the game to back up the shit that I just wrote (when the MC talks to Sage in Tybalt's room):
mc "Are you at least having fun here?"
sa "Um...no?"
sa "Everyone's so fucking fake and my dad even showed up tonight."
mc "Your dad's here?"
sa "Ugh... Yeah. That's why I'm not downstairs and have turned off my phone. I'm avoiding him."
sa "He's just here looking for new business opportunities and kissing asses. It makes me sick."
And Sage's dad when he's talking to some preps:
Sages Dad: "It's been fun chatting, but I must excuse myself."
Sages Dad: "I still have to chat with Dr. Johnson, Will Burr, Sir Gregory and Professor Burke before the night gets older."
Sages Dad: "And can you believe that I've yet to find my daughter in this crowd? I was under the impression she'd attend the party."
Now yes, we know Sage said her father bottles up his emotions, she's talking about him talking about problems, not about him being able to talk to people at a party. She also, as quoted above, said he's "looking for business opportunities and kissing asses". That's what he was doing, trying to ingratiate himself with other people at the party.
Dude, you're fixated on the idea that he doesn't show his emotions, you're missing the point. Looking happy at a party is not about showing your emotions. Talking to family about problems and things like that is what Sage is getting at.