Rattle,
.
"Do you recommend using the coordinates published in a NOTAM, or basing a TRA on where you think is should be? Could be tricky to defend yourself if you make up your own centre".
If presented with the same scenario I would recommend getting in touch with the controlling authority and asking first - something along the lines of "I've been tasked by XYZ TV company to get some footage of the incident at blah, do you mind if I...... etc, etc, and does your ASU have a freq I can talk to them on to avoid getting in anyone's way".
Saves a lot of
all round.