FAA Regulation

No, the other people in the park are not on notice.  Yes, as long as the park is not busy enough that it would be considered an open-air assembly of human beings.

you may fly your drone in the TFR since your company is sponsoring a team at the race. flying your drone is allowed if you notify all non-participating people of the closed course UA operation. the TFR applies to all ...

Use a “buddy box” system with two controllers. Use a radio system to instruct the non-rated pilot. The Remote PIC cannot supervise a non-rated pilot.

An injury requiring an overnight hospital stay.  Minor bruises. Scrapes and cuts bandaged on site.

The FAA does not allow the use of ADSB-out for sUAS. Anytime you are flying in controlled airspace. Only when flying in a Temporary Flight Restriction.

the Remote PIC.  the controlling agency. Air Traffic Control.

Turn down the intensity of the light.  Look down at your controller screen to fly the drone and find the obstacle. Turn off the strobe light.

The owner of the aircraft. The operator of the aircraft. The manufacturer of the aircraft.