You configuration to enable debugging is correct but there is no point in adding it to traffic_logstat, it will have no effect. The debug output should be placed in the var/log/trafficserver/traffic.out file.
I need to check my notes (it's been a while since I worked with this) but I think you iptables rules should be interface dependent (as with ebtables) to allow packets to escape after going through ATS. I also don't recall using divert. Did you set the /etc/sysctl.conf value? You might find this interesting - https://www.dropbox.com/sh/h7erczfbt8ug8kn/cMyk4ukVSg?m - it's a presentation on transparent proxy.
