Issue disabling Discrete GFX from Command Line in MacBook Pro 2011 Hig

As per the title I am attempting to disable the AMD discrete card so the machine uses only the integrated card. I originally went through the graphics card recall for this machine however as expected the replacement discrete card has now failed again.

I was able to install gfxCardStatus initially and if the machine boots using the integrated card and logs into the user account this application runs immediately and switches the card. The issue recently is each time I boot the discrete card is being used whilst previously the machine would boot with the integrated every 3-4 combinations of being forced to hard shutdown. At this point I am unable to boot into the recovery mode or internet recovery mode as after the bar has filled almost completely full the screen goes blue and a hard shutdown is required.

I have gone through the steps of resetting PRAM and SMC.

The main issue by way of a fix is I cannot get the machine to enter single user mode using cmd rs. Now I know the file vault is enabled and I need to disable that however I cannot do that as the combination cmd s also does not work. Nor does entering via verbose mode (cmd v). In each case above I am presented with the screen attached for a quick few seconds and then the machine continues to boot to the log in screen. I am also not able to enter either internet or system recovery mode. I can get to the spinning globe, connect internet and upon progress bar completion the machine hangs. I can run a hardware diagnostic and this returns no issue.

I feel my issue is relating to the file vault as that seems to be the first error returned from the screen attached. I would be grateful if someone has experience or knowledge of such issues could take a look at the attached and discern what appears to be occurring here and a possible work around to disable the discrete card and default the machine to booting up using only the integrated card.

Feel free to ask any further information you need and I am grateful in advance for any insight or possible solutions here.