How do I rectify this? I downloaded and installed and the DLC's arent listed in the menu

The DLCs are included in the GOTY installer. You don't have to install them separately.

So we just install the additional GOTY files and we get all the DLCs, yes?

Just install the GOTY version of the game. Nothing else is needed. Access to additional content (like wallpapers, avatars etc.) is possible through your web browser. Just point your mouse on your nick on top of the screen, choose Games, find Witcher 3 GOTY and click on it. The goodies are on the right side of the screen.

So GOTY edition also includes that free DLC content?

Includes all:
The Witcher 3: Wild Hunt (base game)
The Witcher 3: Wild Hunt - Espansion Pass
The Witcher 3: Wild Hunt - Free DLC Program
The Witcher 3: Wild Hunt - Hearts of Stone
The Witcher 3: Wild Hunt - Blood and Wine

GOG really needs to fix the list when you're looking and mark those off if you've bought the highest compilation and it includes them. So, I know it has the base, hearts of stone, and blood and wine. I'm not sure about the Free DLC as when I look at my game list it shows a non GOTY version of Witcher 3 and the DLC content but says I need Witcher 3: Wild Hunt to access. This leave me a little confused. Again, its not the only series of games that has this issue when you purchase a gold/ platinum, GOTY, etc.

I'll assume its included; but damn, I could be wrong.

Yes, the GOTY edition includes everything, and it's all installed at once.

Ok, thanks for clearing it up.