Thanks.
It looks like, when the Black Pill and Bothrioc Anti-Oil items were added, they were intended to be expansion content to the Bothrioc Quest on Myrellion. These items will unlock in select Xenogen or Steele Tech vendors (depending on who you gave the Bothrioc Genealogy to) after receiving the respective e-mail. Those e-mails are sent out two weeks after giving/selling the genealogy, so there was a timestamp flag added for that purpose. Older save files that already completed the quest wouldn't have that flag, so the mail is sent right away instead, bypassing the waiting period.
So this is working as intended. Though after reviewing the content, I fixed some minor issues and added a Codex Log note about the research duration for clarity.