Chewies medal is explained because Leia is holding it as she dies in this edit. Therefore, it represents both Leia and Han for him (the medal belonged to Han originally)
I get that she’s holding it in a few frames, but…so what? Han didn’t care about the medal; no one cared after they were handed out - they were never seen or mentioned again. Chewie hasn’t been moaning this entire time about being left out. Chewie didn’t care about the medal, Han didn’t care about the medal. Why would the audience? (Outside of the fact that “How could Leia forget Chewie?! He was sitting in the Falcon when Han flew it back to the Death Star!”)
If they wanted to give Chewie something to remember Han by, how about Han’s blaster? How about the dice? How about giving him the Falcon instead of Rey? Heck, the Falcon was where Han and Leia first kissed, so it “represents both Leia and Han” too. Give Chewie something that represents him and Han and their relationship; or at least something that the audience is emotionally invested in.
It was lazy fan service in a movie that was already overstuffed with it.