Your PI readings are definitely within the acceptable range, but still crappy.
Your PIF readings, however, are over double the acceptable range.
As far as if you want to keep using it or not, that's on you. Personally, I would not use that copy any more. I would, instead, burn ANOTHER copy with the EXACT SAME SETTINGS as before and scan THAT with Kprobe to see how it comes out. You're an adult though, you've been presented with the risks and possible outcomes, so you are free to make whatever decision you want. Like I said though, I personally wouldn't keep using it. Burning another copy may yield entirely different results, most likely better than before.
You want your PI reading to have a MAX less than 100 with an AVERAGE less than 5.
You want your PIF reading to have a MAX less than 4 with an AVERAGE less than 0.20
Your PI reading had a MAX of 31, which is pretty good. The AVERAGE was 4.67, which kinda sucks, but IS still within parameters.
Your PIF reading had a MAX of 8, which is double the recommended parameter. The AVERAGE was 0.48, which is OVER double the recommended parameter.
All four of those numbers do play a factor in your chance of getting flagged, but not a single one nor a combination of any or all of them fully guarantee your safety or demise.
Lemee see if I can pull up a PM I sent to Dinoh a while ago...
Huh can't find it. I'll scan one of my disks and show you what results can look like after having the drive "learn" how to optimally write to the disks.
Edit - If burning another copy gives more unacceptable results you can try disabling OPC in the settings in imgburn (tools -> settings -> write -> uncheck "perform OPC before write")