I took Dogmeat with me to complete the Nuclear Option mission and after it was finished and I got teleported to Mass Fusion, Dogmeat didn't come with me. Then I ended up taking Preston back as a companion and had Dogmeat sent back to The Castle...but he's not there or actually anywhere. I've been to every settlement to look for him, placed down doghouses in them, checked them another hundred times, and he's just not showing up anywhere? I'm worried that he got stuck down in the Institute when it blew up (he's holding a bunch of important weapons)

Dogmeat disappeared when I entered secret vault 81 and sent him home. I didn't want him getting bit. I ended up reloading, manually dropping him off in sanctuary, then running through by myself. He also got locked up at the entrance to the fort when searching for Kellogg. I've had him get stuck while swimming, and stuck in a floor before. Major pain after spending points on lone wanderer and the attack dog perk. Save often. Check for Dogmeat every time you go through a loading screen.