The Sentinel and QC Flight RB5 are drones for software development - they are a reference so ultimately so you can build your own drones from our components. From your questions, it looks like you are looking for a more complete system.
We need a 3-axis gimbal with 4K/8K camera, IR and laser rangefinder for testing. Which gimbal with 4K/8K cameras, IR and laser rangefinders are supported. Any suggestions?
No
We need precision landing on a moving base station (RTH) in wind. Does the platform have Dynamic RTH?
No
What is the IPxx rating?
None
Is the SDK open source?
Yes, see https://code.modalai.com
(based on Pixhawk/Python) and would it be compatible with Autel, Parrot or Aurelia?
The flight controller is PX4
It would not be compatible with Autel, Parrot or Aurelia