I installed the offline-download version of the deluxe edition and all the DLC, but when I started it my anti-virus stopped it and quarantined a file called "Drop.Win64.RoamingInject.11510", and then made me restart my computer.

Is it a false positive? Or is there a virus in the offline download version?

I probably have the same problem:

After installing the game offline, when first starting the game (also offline) the program file "LEGO DC Super-villains_DX11.exe" is deleted.

After this,when trying to start the game, I only get the message, that the file is missing.

Update:
I deinstalled everything, than installed only the main game (Offline).
Now I can start the game.

Not sure, if the problem lies within one of the DLCs.
For now, I won't install them until I finished the main game.