Who could be the relative? The landlady might be 10 something older then Zeno, at the highest. Maybe a sister? Maybe a cousin? Still not much sense in their dynimics where they barely know each other and they barely speak outside the 2 events. Anne is a runaway from a cult. Her and Zeno clearly don't know each other when they meet. You should somehow rework the whole encounter making anne.. mother i presume? Be like Zeno's ex-wife. Still weird, and Anne seem a bit too old to be Zeno's daugher.
The last woman is a ghost, it seems. Or an allucination from Zeno's brain tumor.
I don't know where some people see incest. And the question is: for which character. Their past is blurry, but even if you add this to account, there is no logic for incest.
As you said, Lauren's age is too young for her mother, could be sister? Nope. He didn't know her when he entered laundry room.
Anne? Too old to be his daughter, that leaves sister again? Again nope.
Third story I will even not comment.
It's tough to guess Zeno's age, but if we (both) guessed it similar, it's pretty accurate guess (÷/- 5 years)