Do Alliances Share Commendations?

Hey, pirates! I was wondering if anyone knows for sure if alliances share commendations, namely turning in that Chest of Fortune. My friend and I completed a Siren's Song and were keeping an eye on this dude that was working on the skelly fleet. He finished shortly after we did, and it lined up perfectly. I was taking that chest, one way are another in true pirate fashion! Well this guy sounded DONE. He was tired and ready to log out and said he didn't want to fight. I leveled with him and told him that I totally understood that fatigue and empathized, however, he did opt into high seas, and I wanted that chest. I told him he could simply drop it off the back for us and he'd be able to keep his huge stack of loot (this man had 3 athenas and a bunch more). He suggested alliancing so when he turned in the Chest of Fortune, my friend and I could get commendation progress too. Now I've been playing since season 6, and I wasn't so sure about that. I admit my ignorance on this topic, but to be safe, I told him we'd alliance and WE would turn in the chest at a different outpost. That way, we were guaranteed commendation progress. Well, he was confident in his knowledge that commendation progress was shared. Good on him. As much as I wanted a good fight, I could hear it in this man's voice. He needed to log off, and there would be plenty more scalliwags for my friend and I to pillage! I'm wondering if anyone can confirm. Did he also get commendation progress?