  Vanadium tetracyanoethylene (V[TCNE]$_{x}$, $x\approx 2$) is an organic-based
ferrimagnet with a high magnetic ordering temperature $\mathrm{T_C>600 ~K}$,
low magnetic damping, and growth compatibility with a wide variety of
substrates. However, similar to other organic-based materials, it is sensitive
to air. Although encapsulation of V[TCNE]$_{x}$ with glass and epoxy extends
the film lifetime from an hour to a few weeks, what is limiting its lifetime
remains poorly understood. Here we characterize encapsulated V[TCNE]$_{x}$
films using confocal microscopy, Raman spectroscopy, ferromagnetic resonance
and SQUID magnetometry. We identify the relevant features in the Raman spectra
in agreement with \textit{ab initio} theory, reproducing $\mathrm{C=C,C\equiv
N}$ vibrational modes. We correlate changes in the effective dynamic
magnetization with changes in Raman intensity and in photoluminescence. Based
on changes in Raman spectra, we hypothesize possible structural changes and
aging mechanisms in V[TCNE]$_x$. These findings enable a local optical probe of
V[TCNE]$_{x}$ film quality, which is invaluable in experiments where assessing
film quality with local magnetic characterization is not possible.
