Positions reporting issue between voxl and Px4

[tahawaru]

Hi,
We have the following Rb5:
system-image: 1.7.1-M0052-14.1a-perf-nightly-20231025
kernel: #1 SMP PREEMPT Thu Oct 26 05:24:02 UTC 2023 4.19.125
hw version: M0052
voxl-suite: 1.1.2

Here is our problem:
We have a mavlink based GCS and would like to get the position of the drone in the fixed frame defined by the QR-code like tags. We are connecting over port 14550, but can only get the PX4 local frame. The tag information is set in the tag locations file and the appropriate parameters in the voxl-vision-hub.conf are also set.
Question: How can we get the current position of the drone in the fixed frame defined by the tags, preferably over mavlink? We're assuming there's some extra config somewhere that we are missing, since clearly the incoming setpoints can be translated between the coordinate systems.

Thanks