It's good that I anticipated that this achievement might be lying in advance, and made a contingency plan. It's also sad that stuff like has happened enough times that such is a reasonable and recommended thing to anticipate:
Since I had converted Champa after annexing them, I was able to release them in Mahayana and get the achievement. This could easily screw someone out of an achievement they earned.
Since I had converted Champa after annexing them, I was able to release them in Mahayana and get the achievement. This could easily screw someone out of an achievement they earned.