There’s a lot of interesting rumors about Rogue One: A Star Wars Story in the cameo department. One of the things with Rogue One is that it has had a lot of writers and has had a lot of hands in the pot at this point. We don’t know what cameo they went with and what still needs to be filmed on that front. There’s a lot of assumption here based on the various cameo rumors that appear to have been pitches or in development, even while the cameras were rolling.
We have heard of a cameo moment that pretty much has Han Solo playing a BoShek type that simply refers the rebels to people to hire. There was a rumor that Jabba the Hutt brokered information to the rebels. That might explain the rumor that they wanted the young Han Solo role cast so he could have a cameo in Rogue One even though the Solo film will take place about eight years before Rogue One.
There was another rumor that most of the bounty hunters from The Empire Strikes Back appeared in the alternate to this sequence. That means Bossk, Dengar, 4-LOM, Zuckuss, and IG-88 along with a few bounty hunters from The Clone Wars. Boba Fett is also mentioned for this stuff and one description makes us think Cad Bane is included here.
A weirder rumor was that Yoda was part of the cameo segment on Dagobah itself. He doesn’t help them but sends them on their way.
Slash Film broke the story about the plot for Rogue One and when they did they stated:
The story follows a group of bounty hunters who were hired for the job.
My thinking at this point is all of the cameos rumored or pitched pertained to the hiring of those bounty hunters. It seems like Donnie Yen and Jiang Wen are the two bounty hunters the rebels eventually hire based on the visual clues pertaining to their costumes. I think if these cameos are interchangeable, it would seem the cameo role is meant to light the way for the hiring of the bounty hunter mercenaries that are going to help the rebels obtain the plans to the Death Star.
It will be interesting to see what cameo ends up in the film if any of them!