When I finish the final quest in the original game, Take it Back! the ending cut scene plays narrating the general outline of my story. I am then returned to the purifier room and left to either stare at Sarah or lie on the ground shaking, depending on which decision I made.

This is a noted bug on http://fallout.wikia.com/wiki/Fallout_Wiki and I tried doing what little they offered as suggested fixes, that being not having items on me that I shouldn't (such as non degrading items from the Anchorage simulation) still the results were the same.

I likewise have tried numerous console commands, from force completing the quest to teleporting myself to Elder Lyons, still non of these things trigger the events that lead to Broken Steel.

As a side note just in case anyone wondered, Broken Steel is most definitely installed as is evident by my being level 30 and encountering Enclave Hellfire troopers.

Any advice would be appreciated, thank you in advance.

Do you have a custom race? If so, you'll need the Custom Race Ending Broken Steel Override from Nexus.

Oh my god I think that's it, thank you so much