You were right, the problem in this case was likely due to oil seepage from the cylinder head gasket that I had not detected until recently (the wires were saturated). I will be monitoring regularly (and maybe try to create some sort of shield to protect wires just in case) in the future.
I ended up purchasing the Denso 234-9038 Air Fuel Sensor from Amazon This is the same one my mechanic had recommended and I used last year on the driver's side.
Thanks for the quick follow-up. That was my thought as well, but I was wary of the lightning striking twice and the fact that there was no oil leakage (at least to the best of my knowledge/memory) on the first sensor. Just trying to be proactive. I will keep my fingers crossed.
P.S. I love...
I have an annoying O2 sensor code P0133 "O2 Sensor Circuit Slow Response Bank 1 Sensor 1" plaguing since Dec. 2022. At that time I was getting two codes (P0133 and P0031) and switched the sensor with the B2S1 to see if it was the sensor. Sure enough, the codes switched to Bank 2. Great! I...