Yes, U1 should be able to passthrough MQA from native Tidal playback, if volume control is OFF and resampling for 44.1kHz and 48kHz are disabled for firmware 8.* and earlier. (This is from my understanding, although we don't have a MQA DAC to test with yet.)
A scenario that does not work would be using AirPlay: if you use Tidal native app then AirPlay to Lumin, MQA integrity is destroyed because AirPlay is 16/44.1 only, while Tidal MQA is delivered in 24/48 or 24/44.1.