I was able to finally get the guide to import with my IPTV. I used the internal grabber.
I enabled the internal grabber in TVH
https://ibb.co/kG96wm
Then in the settings in TVheadend Server 4.2
It was a simple as setting the xmltv source type to WEB, then putting the url in the xmltv web location.
Then back in the web-viewer for TVheadend, i clicked on Re-run Internal EPG Grabbers.
It took about 5 mins to complete but I was watching the log window and it finally popped up!
I might not have been waiting long enough previously and was making changes before it could complete. Then once I saw this in the log window, it took another few mins before I saw the guide import the data in kodi.
Now I just hope this runs automatically every so often to keep updating my guide.
this was the output from the log.
2018-01-17 16:55:28.719 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: grab took 292 seconds
2018-01-17 16:55:29.071 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: parse took 0 seconds
2018-01-17 16:55:29.071 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: channels tot= 81 new= 0 mod= 0
2018-01-17 16:55:29.071 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: brands tot= 0 new= 0 mod= 0
2018-01-17 16:55:29.071 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: seasons tot= 47 new= 47 mod= 47
2018-01-17 16:55:29.071 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: episodes tot= 254 new= 23 mod= 30
2018-01-17 16:55:29.071 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: broadcasts tot= 254 new= 40 mod= 21
2018-01-17 16:55:29.071 xmltv: /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file: grab /storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file
2018-01-17 16:55:29.073 spawn: Executing "/storage/.kodi/addons/service.tvheadend42/bin/tv_grab_file"