CEL - Code 28, knock sensor. Help?

[Dza]

Hey guys, I need some help with a Check Engine Light code and resolution. I have to pass a federal inspection in the next 31 days, and a CEL probably won’t help much. I did a search and found some info on replacing knock sensors, but I jut have a few followup questions.

The code shows 28, Knock sensor 2 (LH): Abnormal voltage in knock sensor monitor circuit. Lucky me, the harder one to get at!

Here are my questions for you:
- Do I absolutely have to replace my knock sensor, or will replacing it just have the new sensor show a voltage error?
- Can I just reset the code and hope that it doesn't come back? Never done that before, but I found procedures on how to.
- I damaged the connector on the positive terminal of my battery the other day. Would this CEL be related at all?
- I hear that you’re supposed to, but is it mandatory to replace both knock sensors at the same time?

I just brought this car up from the US. She’s used to gas from her old home, but I was sure to use premium (higher octane) here with a shot from the bottle of fuel additive that the previous owner gave me. The gas was in the tank for 7 days before the CEL came on, so it may be unrelated.

I just need to get the car past inspection, and that would be difficult with a CEL showing. I hope that I don’t have to replace the knock sensors, but I will do it if I have to. Any info you guys can provide will be most appreciated.