Whenever I change LNB settings in my receiver, i lose signal and have to re-scan to bring it back, actually run a scan, not quite sure from your posts if you're actually running a scan after changing the LO or not, or just looking at signal and quality levels. You could try setting the LO setting to 10600 and then rescanning 83 W to see if it works, it won't hurt anything. If it doesn't work, just set the LO back to 10750 and then rescan the one sat, 83W, again, and all would be back as it was.
10600 is the most common LO setting, would be quick to try and worth doing. I don't have a Micro so I can't tell you how to do it on that, but in my receiver it's real easy. Ya never know, I have a cheapo Ku LNB here that I bought new [which I can't seem to find at the moment, otherwise I'd post a picture] that states on the label and the box that the LO is 10750 but it only scans all channels on 10600 and it's a universal even though it doesn't state that it is. Probably the best thing to do would be to put the Avenger PLL LNB onto your dish. I have that same LNB and it works real good. One thing you could check that I don't think was mentioned is that your LNB voltage for that sat. is set to 13/18 V and not just 13 or 18 alone, if it's not set to both it'll only scan one polarity and not get all the channels, Although I think the three you're missing on 83 W are the same polarity as the one you do receive, not sure. Make sure your 22 Khz is set to on or auto too, as was mentioned in an earlier post. Those settings should all be on the same page as the LO setting.
If none of this helps you, [which is very possible!] I'm sure that with the new specs you posted that Primestar31, Waylew and everyone else responding to this thread will be able to figure out your problem, they're all very very good with this stuff. Primestar31, Waylew, and many others here have helped me out more than once, I don't think there's anywhere on the net that you could get better help than here.
Stick with it and with the great help here you'll get it working soon and before you know it this stuff will be easy for you!