Hi Danielle,
I cannot tell for sure, but the fact that it’s using a custom field is a very good news. The Meta Data is the same as a custom field, so using the custom field solrting option is the way to go.
I would try these configurations:
– Config1: https://i.imgur.com/btObyBc.png
– Config2: https://i.imgur.com/NIFOil0.png
Let’s hope that either of these work, and the meta field does not contain a serialized object of any sort, but a numeric/string value.
Relevance ordering is a bit complicated to explain fully, but it calculates a relevance number based on the phrase occurence in the selected fields. Some of these factors can be adjusted under the Relevance Options panel.