Do I need to use the internal +3.3V regulator to power VL on the MAX14827A?

The VL input pin is internally separate from the V33 output pin. You may apply any voltage between 2.5V to 5.5V to the VL pin to define the logic input/output levels, regardless of V33 operation. Please be sure to bypass this rail with a 0.1uF ceramic capacitor as close as possible to the pin. Also, note that the V33 LDO can be disabled via SPI, but not via pin-mode.