Yes, it actually depends on how you define your UQLink parser. In my example above, I assume the output is N\times2 matrix, but it is also common to define the parser with multiple output arguments (i.e., function [Y1,Y2] = myParser(...)).
If that’s the case, indeed you simply replace the relevant lines with [~,Y2] = uq_evalModel(myFEM,X) (as you did, but simply get the second output of interest, assuming it is the tensile stress).