  Monolayer FeSe/TiO$_x$ and FeSe/FeO$_x$ interfaces exhibit significant
superconductivity enhancement compared to bulk FeSe, with interfacial
electron-phonon coupling (EPC) playing a crucial role. However, the reduced
dimensionality in monolayer FeSe, which may drive superconducting fluctuations,
complicates the understanding of the enhancement mechanisms. Here we construct
a new superconducting interface: monolayer FeSe/SrVO$_3$/SrTiO$_3$, in which
the itinerant electrons of highly metallic SrVO$_3$ films can screen all the
high-energy Fuchs-Kliewer phonons, including those of SrTiO$_3$, making it the
first FeSe/oxide system with screened interfacial EPC while maintaining the
monolayer FeSe thickness. Despite comparable doping levels, the heavily
electron-doped monolayer FeSe/SrVO$_3$ exhibits a lower pairing temperature
($T_\mathrm{g}$ $\sim$ 48 K) than FeSe/SrTiO$_3$ and FeSe/LaFeO$_3$. Our
findings disentangle the contributions of interfacial EPC from dimensionality
on enhancing $T_\mathrm{g}$ in FeSe/oxide interfaces, underscoring the
importance of interfacial EPC in $T_\mathrm{g}$ enhancement. This FeSe/VO$_x$
interface also provides a platform for studying the interfacial
superconductivity.
