Altitude Hold using SF000 Lidar


I am using Lightware SF000/B (50m) and Hereflow with Cube Orange.
I have setup sf000 in I2C as RangeFinder_1 and hereflow in CAN2 as RangeFinder_2 (both facing downwards)

I’m getting consistent values from both lidars when kept on a bench.(see image below)
Screenshot 2022-01-28 031309

Now, I’d like to know which rangefinder will EKF use when the copter is hovering below both RNGFND1_MAX_CM and RNGFND2_MAX_CM values.

And which data is displayed as sonarrange (see image below)
(It looks like raw data from rangefinder1 but it could be estimated range from EKF, correct me if I’m wrong)

In the Article Target Altitude Modification, its mentioned that rangefinder data is only used for Target Altitude and not Estimated Altitude !
Rangefinder data (if in range) is supposed to more accurate than GPS and BARO (correct me if im wrong) so shouldn’t EKF use RangeFinder data for estimation as well ?

Does parameters EK3_SRC1_POSZ: and EK3_SRC2_POSZ make the above changes so that EKF uses RangeFinders for Estimated Altitude, and does primary, seconday, tertiary parameters(SRC1 , SRC2, SRC3) relate to EKF Lane switching?

And Lastly why doesnt EK3_SRC1_VELZ include RangeFinder