I'm guessing you may have damaged the auto and bypass switches while soldering. I did exactly that with my auto switch. I used magnet wire for the ground bus and overheated to burn off the insulation. I was able to rescue it by reheating the sunken terminal and pulling it out of the switch somewhat, though I'm on the lookout for better quality switches. Try disconnecting the wires from the switches and shorting them to ground manually.?
Your SWR and power readings are probably off due to the inferior Shottky RF-sensing diodes. Mine is also off (Ali-Express, Hisonauto). I ordered some 1N5711 diodes from Mouser. I'll have them early this week and I will post an update.
The Ali listing for my tuner claimed that it would tune down to 1 W. It seems to do that just fine using my KX3. I did not do the binocular transformer mod and programming change.
K9NUD-Steve