For a conference
A conference can commission the work as a member benefit — one process, every member campus, every international student on scholarship. Each member campus uploads its records once; Vesper does the rest.
For a campus
The campus keeps its system. The campus keeps its staff. The campus uploads its 1042-S and Bursar data and monitors progress. Vesper reads the records, does the allocation, and brings the professional work. The campus is not asked to review, approve, or chase anything, or to become a tax firm.