Lora Wifi v2 disable display and wifi

Hi, I am using the library https://github.com/HelTecAutomation/ESP32_LoRaWAN with Heltecs Lora 32 (v2). I Need turn off the display for some cases, and on/off wifi for some cases.
Vext I am using to connect a peripheral (out=3.3) and use gpio21 to turn on when needed. How can disable the display and the wifi at default and turn on/off?
I see ESP_LoRaWan.cpp and, for some methods “display” run: digitalWrite(Vext,LOW/HIGH); but Vext is no defined in any class.

The pins are defined in this file. https://github.com/Heltec-Aaron-Lee/WiFi_Kit_series/blob/master/esp32/variants/wifi_lora_32_V2/pins_arduino.h