91 Pudge unlock?

I took a year off so pardon if this is a dumb question. How do I get the diamond Pudge? I thought that by completing his moments, I’d unlock it but I was clearly wrong.

Player programs under the collect tab

1. Acquire Rookie Pudge.
2. Do all Stage 1 Moments
3. After unlocking Stage 2, do whatever combination of Moments/Missions gets you to 50 Pudge Points.
4. PROFIT!