Yes that’s the issue, it’s matching by episode name first as that’s the most common way to match shows. This topic outlines the order of matching used by MCEBuddy: Metadata matching, extraction, renaming from files and downloading from the Internet
One thing you can try is to change the matching order from Name to AirDate in the Metadata corrections page from the Conversion task → Expert settings page although I think that may not solve your issue either since you don’t have an original broadcast date/time either.
This may need a new feature to allow users to select episode/season number as the matching priority rather than just name or date.