He did avoid her. He intentionally stayed in his area because of Lazio. It was Clinton who moved around. It was the photographers who took angled shot diagonall across the stage. Proof? If people are anywhere in the picture, then it had to be an angled shot, for a wall stretched all the way across stage immediately behind them.
Watch the debate again and watch the producer desperately switching camera shots trying to get a shot of her being “stalked.” This was a setup between the Hillary campaign and the network that ran that debate. NBC?
At the first debate, the back of the stage camera was angled to show both candidates being the same height. But, oops, it also caught her podium light coming on at the start and going off at the end.