"ended up knowing" is a correct and usable phrase in written English.
It is typically used to describe a situation where someone unexpectedly gained knowledge or understanding about something. Example: "I never intended to learn French, but I ended up knowing the language fluently after spending a year studying abroad in Paris."
A middle-aged male accountant had asked for the test, after his brother's doctor recommended all family members to be tested following his DVT; the brother had not told him much about the condition, and the participant ended up knowing he was positive but did not know the marker.
"They're faster than stock cars, and we ended up knowing all the drivers".
"The Americans ended up knowing and trusting their French colleagues, and we ended up with objects from 18 different museums".
I used to spend a lot of time on probably one and a half miles of coastline, and ended up knowing it like the back of my hand.
They had a track called "Goddess of Love" all ready to go, but when a new ending had to be shot for the movie — test audiences had flatly rejected Hughes's original scene, which had Molly Ringwald picking Jon Cryer over Andrew McCarthy — O.M.D. was left with 24 hours to compose the song everyone in America ended up knowing them for.
A few of the pictures were of the mother, but most, taken after her death in 2000, were of her belongings: clothes, combs, makeup, leftover things from a life that Ms. Ishiuchi ended up knowing most intimately through its material remains.
We end up knowing which variables predict an outcome, but we don't know why.
So games of induction, they work by building up on the length of the game, and we're ending up knowing that we're done.
We end up knowing them not as subjects but as fellow day-trippers, and it is they, not the interviewer, who lead the trip.
And within the entertainment business, it is such a small world that you all end up knowing each other.
