How can I reference a table with tens of thousands of job titles from a separate workbook in the job title keywords field?

You cannot directly reference another table's data in the job title keywords field due to a 100-reference limit that applies even to cross-workbook lookups. However, you can use the Lookup Multiple Rows in Other Table action to pull job titles from your separate workbook into your current table, then manually copy the most relevant titles (keeping under

100. into the job title keywords field. Alternatively, break your ICP titles into multiple buckets and run multiple passes with different sets of up to 100 keywords each, or pre-classify titles upstream into a smaller, normalized set.