My rudimentary understanding is that the basic issue is the same in that we need incredibly high energies for experiments to probe quantum gravitational effects, thus any theory of quantum gravity is going to run into this issue, be it string theory, LQG, etc...
This is not the be all and end all however, for example there is reason to believe that by observing evaporating black holes we may detect a certain type of radiation predicted by LQG, this experiment is only in it's very early and highly theoretical stages however.