Two possibilities come to mind.
1) Yes the vWLAN server can set the Transmit power level for the APs as a % of full power.
2) The external antennas are band specific even though they look the same. You should check if they are installed into the correct connectors (see diagram)
Also, you didn't mention which band you were testing. The LG you mention can do both. A good idea during testing is to create 2 SSIDs, one for 2.4G and one for 5G, that way you know what band the test device is connecting to.
You should always test further than 3 meters from the AP. The pattern for typical antennas leaves a dead spot near the AP. Also, your tests from 90 meters (~300 feet) look good. You are also testing APs with internal antennas versus an AP which requires external antennas. I would add this to everything from the previous poster.
Please also verify you are using 802.3at POE+. 1940s require POE+ not 802.3af POE due to higher power radios for long distant mesh links.