There is zero chance of that happening. Western "media" got that wrong. Baidu said "Baidu will seek cooperation opportunity with Tesla on Robotaxi based on Tesla’s specific need and timetable."
It's a misconception that they would use Tesla tech, it's the other way around if anything.
They also recently said that they believe they are at least 3-5 years ahead of anything Tesla has.
Yes. Apparently they have a fleet of around 500 RTs today.