@Fran-Diox Thanks for all your help, we’re up and running. The issue was not the slash (although the slash created another issue), the original issue was the latest version of Monaca Debugger. We upgraded it at the same time as we made changes to the vue router, and thought something went wrong with our configuration. Yesterday, we realized that in the Debugger, once you get the loading bar, the file sync would stop and freeze somewhere in the middle (ex files 2 out of 13) for about 30 seconds to a minute, after which the app would open to a white screen with the errors I originally provided. Clearing the cached files did nothing, but uninstalling and reinstalling the Debugger app fixed everything.
So if for some reason someone notices that their app has stopped loading for no good reason, try uninstall and reinstall.
Thanks again for all your help, we did learn a lot about webpack and various config settings thanks to this whole ordeal! :)