Data - update migration script to populate tax ids properly for all firm scenarios

Verify tax ids are populated correctly are populated correctly for SPs & GPs. Make updates as required.

Consult with Argus about the different scenarios

**TODOs**
- [ ] Verify tax ids are populated correctly for SPs for all scenarios.
- [ ] Update migration script for SPs if required
- [ ] Verify tax ids are populated correctly for GPs
- [ ] Update migration script for GPs if required

Start by consulting Argus about the SP and GP tax-ID scenarios, then locate the migration script that populates those values. Verify the existing results for every stated scenario and update the script where required; done means SPs and GPs have correct tax IDs across all scenarios.

Written by the indexing model from the issue text.