Pixhawk 2.1 using Here GPS and exposing I2C and serial port

Ok alot of confusion here.

For my new quad build I am planning to use a LidarLite v3 and a PX4Flow module (scavenged from my older quad build) with the Pixhawk 2.1 (with Edison in carrier) and a Here GPS.

In addition I need a serial input port available for Mavlink control/interaction with a secondary companion computer (edison being the first) capable of video processing.

Has anyone been able to use either the PXFlow or LidarLite v3 module with there Pixhawk 2.1 (preferable using a Here GPS)?

I have been researching a bit, and from what I have gathered, it seems the latest Arducopter build will only utilize the one I2C port which is exposed by the the carrier board’s GPS1 port, the physical I2C2 port is not used.

Could I then plug the Here GPS into the GPS2 port, so I dont lose access to the GPS1 I2C? Then break out the GPS1 port with a custom connector to get at the I2C? Need I2C for the PX4Flow and LidarLite modules.

I know there have been issues with the LidarLite v3 for low altitude hold, but it worked fine for me in my last build. Since im over budget already moving to a Lightware (pretty expensive) is not feasible.

I cant seem to make out from the Ardupilot forums if using a LidarLite v3 or PX4Flow is currently even possible, even if one gets access to the GPS1 ports I2C connection. Any thoughts?

Furthermore, the carrier board’s TELEM1 port would be connected to my 3DR Telemetry radio, but since my carrier has an Edison TELEM2 would not be available. So would I need to acquire serial access via a break out of GPS2? Or is there a low latency way of talking to the Pixhawk (via Mavlink protocol) through the Edison, for my secondary on-board Companion computer (right now Intel Joule based)?

Since the close quarters collision avoidance system I am working on would be running on the Joule, I need responsive Mavlink access to the Pixhawk to make quick course corrections.

Thanks for any advice!

There is a lot of info in this post regarding your question