OK, let me explain what the Bell theorem says:
It says that reality either
a) does not exist
or
b) is nonlocal and contextual
The paper that you mention, indeed, also shows that nonlocality is not enough, but that contextuality is also needed in order to have reality. (BTW, Bohmian mechanics is both nonlocal and contextual, so you are right that it is not excluded by results of the the paper that you mention.)
Nevertheless, contextuality is usually not considered to be an unacceptable property. What is considered unacceptable is nonlocality. That is why non-real
interpretations of quantum mechanics are widely accepted.
And now comes string theory. Various results in string theory (that have no analog in particle physics or field theory) show that a certain form of nonlocality cannot be avoided. As it cannot be avoided, now nonlocality becomes acceptable. With nonlocality being acceptable, the main argument against reality cannot longer be applied. In that sense, with string theory reality becomes more acceptable.
Even with accepting reality, there is still many possibilities. Nevertheless, an independent argument
http://xxx.lanl.gov/abs/hep-th/0512186
shows that the Bohmian interpretation is quite natural within string theory. (This argument that does not have an analog in particle physics.)
In addition, string theory solves some intrinsic problems of Bohmian mechanics that cannot be solved so elegantly within particle or field physics:
http://xxx.lanl.gov/abs/hep-th/0702060
http://xxx.lanl.gov/abs/0705.3542
Thus, although the things are not yet settled, some results do point in the direction that string theory and Bohmian mechanics are naturally related.