Codes P0157, P0158 and P0441?

Hello everyone,

I have the above codes with my vehicle listed above. I got it at an auction. When I scanned the vehicles, I got the above codes. For the P0158 and P0157 issue, I suspected the bank 2 sensor 2 oxygen sensor and replaced it, twice but the code persists. I have checked my exhaust for leaks but there are no leaks. Also, I want to mention that there were no catalytic converters in the exhaust pipe, hence I bought O2 spacers which fixed P0420 code I got earlier. I tried taking it to local repairs and they all said that buying a new cat will fix all the above code. With the amount of money, I have spent so far to fix the above codes, I will be glad if buying new cats will fix the issues, however, I will feel really bad if after replacing the cats, the issue still persists. Please, I need urgent help. For the P0441 I have replaced the purge solenoid, the purge valve and vacuum switching valve, still the code persists. I have checked for leaks in the vacuum line, but all the hosts seemed intact. When I read live sensor data, I can see that the output voltage from the bank 2 sensor 2 fluctuates between 0.8v and 0.9v. Please, what can I do to have a clear dashboard? The car runs and drives very well apart for the lights on the dashboard. So do P0157, P0158 and P0441 codes indicate absence of catalytic converter in 2010 Lexus ES because, yes, the car has no cat as I stated in the original post? Also, I was told that O2 spacers don't work for many vehicles, 2010 Lexus ES inclusive?