Resolved via Tech Support. For future posterity, issue was specific to RHEL 7 (maybe CENTOS) using an older library than MATLAB expects. Solution was to point to MATLAB's copy of newer library in <matlabroot>. I modified both /etc/bashrc and <matlabroot>/toolbox/parallel/bin/mjs_def.sh to have the following line:
export LD_PRELOAD="<matlabroot>/bin/glnxa64/glibc-2.17_shim.so"