Bingo. You can actually see from the doors they're on
deck 9.
Which is probably what Worf's line was supposed to reflect originally, until somebody failed to read the memo. But we don't know how deep into the ship the Reman transporters would penetrate through that bottom opening in the shields.
Which is right around the top of the ship's
tallest vertical turboshaft, starting directly under the saucer shuttlebay. Assuming there's more than one shaft in that position along the width of the ship, one of them could be semi-permanently shut down (hence the non-retracting yet flimsy catwalk), and boom, instant dramatic fight-location.
Hmm. One might assume a turboshaft to have side openings, supposedly crucial to its intended function. But ST5:TFF featured none, either...
Might be simply for ventilation. Air needs space in order to move efficiently. And the shaft did feature lots of billowing smoke that would definitely need to be moved somewhere...
Now, the problem is that the only dialog is that the Viceroy boarded at Deck 29, and Worf sends security there. It's plausible that the Viceroy made it past them and Riker's team was trying to head them off, but that wasn't made explicit, leaving a space in what you could call the nitpicker's window, where there's a subtle contradiction, and anyone who catches it isn't enjoying themselves enough to make the extra mental leap to give the movie the benefit of the doubt and assume the most obvious explanation is true.
To crowbar the shards off the edges of the already broken window, let's study this a bit more. Theoretically, Riker should enjoy access to turbolifts while the Viceroy should not. In practice, though, the latter party could hack the systems to their benefit, gaining access while denying it from the former - and then there'd be a counterreaction.
Think "Let That Be Your Last Oddly Edited Chase Through the Sets" if you can suppress your gag reflex: it's perfectly logical for Bele and Lokai to first leave the bridge via turbolift and then have to resort to running, because they are explicitly capable of controlling the ship's machinery and implicitly capable of making the turbolift car an unviable getaway vehicle.
Here it should make sense for the Viceroy to struggle upwards by whatever means necessary, ultimately having to abandon turbolifts (and perhaps three-fourths of his boarding party, too) and to press forth on foot. Riker would be rushing to meet him, but having to guess where: even if he enjoyed constant access to turbolifts, he'd have to swing up and down, port and starboard like a soccer goalie until finally cornering the Viceroy in a single corridor (while three-fourths of his forces might be in other locations, having guessed wrong).
Alternately, Worf sent a security detail to secure Deck 29 while himself establishing a last stand at Deck 9, the lowest deck where he could be certain to block alternate access routes...
This fun piece of treknology in action is less a sin IMHO than it is a price to be paid for the sins of the movie: it really should raise no antennae
at all if part of a better movie.
Timo Saloniemi