In Fallout 4, Molecular Level, I have the quest to build the Reflector Platform.
I did so, but the quest won't update, so it still reads "Build the reflector platform."  So I can't go on to build the other pieces.
I tried reloading, restarting, rebuilding, trying every building site, talking to Tinker Tom.  Been googling for a day with no results.  No answers on the nexus.  
The quest won't update, and I can't move on.  
Yes, I have hundreds of mods.  If it's a mod, I'll just have to shrug and console cheat my way out of this.  I've lost games in the past to removing mods, not going to risk it again.
Any other possible solutions?

Edit: Even console commands won't advance the quest. It's absolutely completely stuck. Going back to older saves doesn't work. I think I just lost a game with hundreds of hours on it. I hope it's just the railroad that is bugged, maybe it'll work if I go with another faction.