you are the best! that worked! hurra!
for anyone bumping into the same issue:
adb shell into voxl2 mini
wget http://voxl-packages.modalai.com/dists/qrb5165/staging/binary-arm64/modalai-slpi_1.1.12_arm64.deb
dpkg -i modalai-slpi_1.1.12_arm64.deb
wget http://voxl-packages.modalai.com/dists/qrb5165/staging/binary-arm64/libfc-sensor_1.0.5_arm64.deb
dpkg -i libfc-sensor_1.0.5_arm64.deb
into the docker:
./clean.sh
./build.sh
into voxl-px4/px4-firmware/
/boards/modalai/voxl2/scripts/install-voxl.sh
tadaaa