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The enormous increase in mid-IR sensitivity and spatial and spectralresolution provided by the JWST spectrographs enables, for the first time,detailed extragalactic studies of molecular vibrational bands. This opens anentirely new window for the study of the molecular interstellar medium inluminous infrared galaxies (LIRGs). We present a detailed analysis ofrovibrational bands of gas-phase CO, H$_2$O, C$_2$H$_2$ and HCN towards theheavily-obscured eastern nucleus of the LIRG VV 114, as observed by NIRSpec andMIRI MRS. Spectra extracted from apertures of 130 pc in radius show a cleardichotomy between the obscured AGN and two intense starburst regions. We detectthe 2.3 $\mu$m CO bandheads, characteristic of cool stellar atmospheres, in thestar-forming regions, but not towards the AGN. Surprisingly, at 4.7$\mathrm{\mu}$m we find highly-excited CO ($T_\mathrm{ex} \approx 700$ K; 1000K out to at least rotational level $J = 27$) towards the star-forming regions,but only cooler gas ($T_\mathrm{ex} \approx 170$ K) towards the AGN. Weconclude that only mid-infrared pumping through the rovibrational lines canaccount for the equilibrium conditions found for CO and H$_2$O in thedeeply-embedded starbursts. Here the CO bands probe regions with an intenselocal radiation field inside dusty young massive star clusters or near the mostmassive young stars. The lack of high-excitation molecular gas towards the AGNis attributed to geometric dilution of the intense radiation from the brightpoint source. An overview of the relevant excitation and radiative transferphysics is provided in an appendix.

GOALS-JWST: Mid-Infrared Molecular Gas Excitation Probes the Local Conditions of Nuclear Star Clusters and the AGN in the LIRG VV 114