The difference between the 727 wording and the 777 wording , is because these two aircraft have different cargo hold types. Hence different capabilities with regards fire containment, detection, and fire fighting. The fire retardent system on the 777 provides protection for 3 or 4 hrs (can not remember the exact number now!). Now this does not mean that they want you to fly for this long, but it is there to give you some options when on that long over water ETOPS sector etc, or when all the airports around you are too short , fogged in or closed.
Because this 777 was dispatched on ETOPS plan, an ETOPS check had to be preformed prior to departure. Part of this check is to ensure that there is no damage to the holds which would lessen there ability to detect, fight or contain a fire. If damage is found, they must be left empty (can carry empty ULDS only) as Boeing now reckon that the system will no longer certified to contain the fire.