I have completed both projects and played the raid again to get parts for the Regulus Exotic pistol but the Engraved Muzzle did not drop for me! (screenshot attached all other components completed). yes i have checked properly after killing Morozova and all i got is high end loot, please help! 
Hey there @Sushi-Boy. and welcome to the Ubisoft Discussions!
I understand that the item Engraved Muzzle for the project Rats Gnaw Our Bones to get the Regulus didn't drop. This issue should be solved as of the 27-08-2022. If you are still experiencing this issue, please share a video of this with us, so that we can forward it to the dedicated team. The video can be uploaded to any video-sharing website, such as YouTube or Dailymotion.
Hello @Sushi-Boy, we can see on your account what items you have obtained and what items are missing and we can also see recent playtime, but we have no way of knowing what game modes have been played in those sessions, which is why we must ask for videos of these issues occurring for our QA team and Division team to continue investigating.
If it happens again, please try and capture some footage for us and let us know, even if it's just done from your phone, as it may contain something that the QA team can use to reproduce and find the cause of it.
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