Actually I may have worked it out...
I am testing this all at home before we go live and I pulled out another TV to try different combinations of TV.
This time it works - I will happily test it at the pub tonight
Thanks for the help - if this fails - I will get that HDMI to AVI convertor and try to run through the RCA on the 2nd TV instead of the HDMI but it looks like we will be good to go