Typically, shortening barrels from say 30" to 28" still leaves a bit of choke. But you would have to measure the bores from the muzzles back to the actual bore diameter to know for sure because different manufacturers used different reamers, tapers, and configurations. Also, the chokes may have already been reamed or honed by someone else.
I know it's just a Crescent, which isn't really collectible, but another option is to attempt to weld the crack in the muzzles, using a copper plug to back up the weld on the inside. Then lightly clean up the weld on the inside and strike off the outside, and re-blue. It would be important to keep the solder joints of the muzzles and ribs cool enough to keep them from separating. I certainly wouldn't recommend welding on a barrel further back, and even question the practice of using TIG welding instead of solder during sleeving. But pressures are as low as they will get at the muzzles, and if it didn't work out, you could still trim them back. And it would be good practice in case you ever find the same situation and wish to save another gun that is collectible.