In return for jogging my memory, I'll gratify you with an answer.
The sports event is none of your business, but there are no restrictions on photography/video, as is common in Europe, those restrictions are a US exclusive.
One of my daughters competes at a national level in this sport. The best spot is center stage (center mat), but unfortunately that's where the judges are sitting.
So a camera with a 14mm, placed in front of the judges, below their line of sight, is the sweet spot.
Which is why a visual indicator is not a good idea, it would distract the judges. Hence the radio need & the need for distance. 'Cause I'm busy taking pictures from the next-best-spot.
The way I read your statement was photography was not allowed where you wanted to place your camera. Thus if you place a camera there and photograph, you are breaking the rules of the venue. It might not illegal per se, but you are still going against the rules. Sometimes this is justified, sometimes not. Sometimes petty officials will do things like take your camera if they find it.
If you feel that you can place your camera there, you could always rig up a remote video setup that takes the live view from your camera and feeds it into a wireless video feed that you have the monitor where you are standing. You might want to consider pan and tilt servos to change the angle of view (and another servo to zoom in/out) or not, because such things might break, leaving you with no shots.
If you could run a wire, using DSLR commander on an Android or Apple phone would be another option.