as an update, it appears the 3.2v is from the air/fuel sensor and that voltage should be OK. Now I'm not sure if the second O2 is supposed to fluctuate or be more steady?
2008 Corolla with 136k miles. PO said he swapped a hollowed out cat system with one from a junk car. Just got it yesterday, and I hooked up my OTC scanner with live data. The code is p0420, the first sensor reads ~3.2V steady and the second O2 reads between .1 and .9 but changes very quickly...