Data driven categories: use different field if first choice is empty

[gangenen]

 The feature request relates to this post: https://www.photools.com/community/index.php?topic=3868.0

For my camera the image files have values for the standard Model and Make Exif-fields. But for the video files of the same camera those fields are empty. Instead, the Make and Model information are in different fields (H264-fields). Instead of assigning my videos to a Make "other" I would like IMatch to use the H264 fields in case the exif-fields have no values. This way I would not need to copy the Make and Model from one field to another. There is a warning not to write to the EXIF or XMP fields that exist. So I would rather not touch the metadata. And if IMatch could look into a different field in case the first one is empty (instead of assigning a category "other") I would not need to copy and values for Make and Model.