Yes as it`s the same component in both 15" & 17". The only differentiator is the 17" has slightly better cooling thanks to it`s larger chassis. The 17" is also on Apple`s extended dGPU warranty list, which confirms the above.
Realistically your limited to two options; use the Notebook lightly and try to keep the dGPU temperature below 70C or the opposite push it as hard as possible, likely resulting in dGPU failure again (especially with a refurbished LB), forcing Apple to effect further repair, repeat forcing Apple to ultimately replace the system. Personally I would choose the latter as this mess is on Apple in the first place, nor would I choose the easy option of selling the same to an unsuspecting individual.
IMO Apple should have been forced to replace all these affected systems with new units that are fit for purpose, as the design of the 2011 15" MBP is inherently flawed. If you use the 2011 lightly the issue may well never arise, equally if you engage the dGPU frequently it`s simply a matter of time before the Notebook will fail.
n.b. the dGPU warranty extension ends Feb 2016
Q-6