Q.raccoon in garden
It appears we have a racoon in our garden – hollowed out melons, half eaten corn, small dug up holes. However, we already have a deer fence over 8 feet tall, but only the lower part – about 3 feet high is chicken wire, the rest is barbed wire strands about a foot apart. We also have an electric fence around the garden itself. None of this has stopped him.

From experience, if the raccoon finds a food source they are difficult to stop.
Trapping the raccoon in a live animal trap my be your last resort, as would seem you have done the best possible fencing and deterrent.
If you are not able to set these humane traps up yourself a pest and animal control professional can help you.
https://www.gardeningknowhow.com/plant-problems/pests/animals/getting-rid-raccoons.htm