we know Bajoran impulse ships don't have warp speed
We don't even know that there exists such a thing as a "Bajoran impulse ship". In "The Siege", a couple of winged interceptors challenge Dax and Kira's subimpulse raider, and Kira dives into the atmosphere, believing that this will deprive the interceptors of their advantage of having impulse engines. But the episode makes absolutely no suggestion that the winged interceptors would be warp-incapable. And indeed said design is seen in interstellar space, on errands that absolutely require warp drive, in "Preemptive Strike" and "Through a Looking Glass", proving that it indeed has warp drive.
In "Ensign Ro", we see the Bajora terrorist group operate a freighter that lacks warp capability. But later on, we learn that ships of that design are capable of interstellar flight, so the loss of capability must have been due to a malfunction rather than design.
In "Shadows and Symbols", Bajor assembles a fleet of impulse ships, which features a few of the winged interceptors, too. But we never learn which ships in the fleet are "impulse ships"; apparently, the winged interceptors are not.