SC received its contractually due cash amount from VERB/AGP ...$15m.....and then used $4m of that to buy units from AGP just like other participating institutions.
Ignore the then this, then that....as this all happened simultaneously.
Basically SC (with their show of confidence..committing to more units) assured that the deal would be completed.
For shareholders that purchased at higher prices this seemed a very lousy deal.....but from the SC perspective (insiders) the offering price was irresistible so they bought more.