Sure, it seems picky to pluck out one unimportant line. But it's the case throughout, where two supposedly interacting characters are clearly not in the same room, nor having the same discussion. It's remarkably off-putting. Originally written in German, there are some translation issues too. A lot of the time the spoken text doesn't match the subtitles, sometimes dramatically so, often with the actor not bothering to fix a clearly mistranslated sentence.
The worst effect of all this is the timing is destroyed. Jokes that would obviously have worked in its native tongue are awkward and confusing, with the pacing mismatched throughout. For a comedy game, this is a big, big problem - it's very rarely funny, and far more often you're left with the thought, "Ah, I see how that would have been funny if they'd got it right." That's not a satisfying way to react.
There are all sorts of other issues. Really stupid game-breaking bugs, like an object you're meant to pick up at one point being invisible, or a lack of testing, like seeing the location description as, "Enter IACTOR_VILLAGE_JUNGLE_ LEAVETO_CLIFF_DESCNANSE". At one point there's a line of recorded dialogue missing, the sound levels aren't matched, and there are typos throughout.
Another issue that's tricky to get around is the portrayal of various nationalities. This begins in the African port where you don't meet a single non-white character - very odd. But gets a lot more unsettling when you're in India (where you spend the bulk of the game), with the innumerous "hello-please" faux-Indian accents on offer. Some sound realistic. A lot sound unpleasantly like a 1970s sitcom.
The scale here is excellent. It's a big game, with a lot of locations, all designed really nicely. And there's an awful lot to do, lasting ten hours or more. Deck13 don't scrimp in this department, and this is probably why Jack Keane is such a disappointing experience, rather than the more usual dismissible. It's reminiscent of the Runaway games in this respect (but in this respect alone - Keane is never misogynistic) - a big game, lots of effort, but very little satisfaction. I'm prone to love a game where the solution to a puzzle is to have a monkey eaten by a killer plant (don't worry - he survives), and the developer constantly demonstrates a passion for the genre, and the LucasArts games that dominated it. But this time, the game doesn't reflect it.
Later on you're given the chance to play as the female hero, Amanda, offering an alternative perspective on the story. But this arrives so late, and is used so fleetingly, that it feels like a last-minute extra. To have been able to go back and forth between the two throughout would have offered so many more opportunities for decent puzzles, and given the romance story a lot more grounds.
But if anything captures the experience of Jack Keane, it's the gags during the closing credits. I love credit gags - I'm such a sucker for them. And what they've done here is create fake outtakes (Pixar-style). But not a single joke works, each mutilated by horrendous translation and lines delivered by an actor who clearly hadn't been told what was going on in the scene. They're the drifting ghosts of a murdered joke - something that struggles to lead to funny. That's Keane - a potentially enjoyable game, broken by terrible performances, and puzzles that make little sense.