In the film, an Imperial fighter shoots at an Imperial facility, targeting a person in Imperial uniform.
Fortunately we have Jim to explain how this sort of thing happened.
Okay, okay, maybe the Imperial command noticed something was up and ordered the fighter to check it out and shoot anyone who happened to be there. So remember that when a group of PCs think that disguising themselves as the enemy is a good way to sneak around without being suspected. Sooner or later someone might notice that something isn't right, and then even wearing the disguise won't necessarily allay suspicion. Don't let it be a free pass.
[Reminder: Our guest commentators have not seen Rogue One. Part of the fun is seeing how their untainted impressions re-interpret the movie through the lens of our comic.]
Pow. Pow. Pow.
In the final panel, the ship is not shooting at Bria so much as shooting between Bria and the tower. Good for the Empire.
The whole thing actually reminds me of an episode of Andromeda; the warrior guy was off on his own in a ship, and hidden; the main crew was being attacked, and they radioed off a message to him (wide beam transmission), with instructions "do not respond". Naturally, he responded "understood"; all the bad guys proceeded to leave the main ship alone (saving all of those characters), putting himself at risk (and now the other characters had to come back and save his butt).
Unfortunately, Bria's reveal of where she is located doesn't save anyone, and just results in...
Well, it should result in operational security being willing to destroy the dish to stop the transmission, if the transmission has not already been stopped by the destruction of the computer terminal.
Somehow, this version of the "how the plans got to the Rebels" isn't quite as enjoyable as the non-canon Phineas and Ferb episode.
Meanwhile, let me try to guess how the Rebels will finally win here. We know that Jim has talked the GM into letting this planet have exotic forms of ice. Presumably, one of those special forms has a property that Jim knows about, will surprise the GM with, and that in turn will allow the (are we down to only two now?) surviving Rebels to completely obliterate all of the remaining Imperial forces, allowing the Rebels to complete transmission of the plans, even though they die in the process.
And no, you don't get a bonus for the railings when they are completely destroyed by the attacking ship.
— Keybounce
Transcript
Bria: Hey guys, I'm standing out on the catwalk on top of the tower.
Bria: I'm disguised as an Imperial, but I'm actually a Rebel saboteur transmitting secret Imperial data to other Rebels!
Bria: I'm in a really exposed and precarious position here, so don't shoot me, even though I'm an easy target. Okay?
{beat}
Barion Raner (Blue Four): You do realise this is an open channel, right?
{beat, an Imperial pilot}
[SFX]: Pow! Pow!
GM: You know that Dex roll I told you not to make?
Bria: Do I get a bonus for the railing?
[SFX]: Pow!
[SFX]: Kaboom!
[SFX]: Pow! Pow!
[SFX]: Kaboom!
GM: Let me check, this has never come up before.