If the J* crew stated that they were carrying out an RNAV approach for runway 06 surely all you have to do is look to the west for the big jet with its landing lights on? The CTAF procedures were developed by a consultant in DOTARS who had never flown anything bigger than a piston twin. The procedures are inadequate when it comes to RPT jets. If crews fly straight in via the RNAV approach then that is a predictable flight path that everyone can be aware of. As has been mentioned, if you are unsure of where the traffic is, speak up.