To align a DTV dish with a satellite meter, the meter needs to be one approved or setup to use on a DTV system, a cheap one will not work, all it will do is peg out like your seeing on your meter.
To use a standard satellite meter on a DTV system you could use this item, but it will only work on a legacy system.
Code:
https://www.amazon.com/DIRECTV-Alignment-Locator-ACCUTRAC-DIGISAT/dp/B00M4D9AQQ
I would test the DC power inserter with a DVM first, this to see if it has gone bad, you should see about +21 volts DC.
And there will be no DC output from the DTV OEM receiver as the DC power inserter provides all that is needed.
I would first re-align the dish for the correct satellites by going to dishpointer.com and selecting the correct set of satellites, (three choices) this will give you a line showing the correct direction for the dish.
I would also check the system for a switch somewhere inline, this too may have gone bad.