I was thinking more too on how China might feel about RNZN, RNZAF patrols we normally do in the area if/when that occurs. They could effectively kick us out, leaving fiji free riegn to do as they will against rival lesser equiped nations like tonga,samoa ect.
KP Fiji are a sovereign nation they are free to choose relationships with whoever they wish, this is more a failure of NZ foreign policy towards Fiji than anything else, China is not going to expend its Military hardware in Fiji knowing full well that it can be fully isolated and cut off by the USN. Finally you have not taken into account that Fiji & Tonga share the same Royal Bloodlines might not mean alot to you or anyone else but it means the World to those two Countries. Soft power has and always will be the greatest tool MFAT as part of NZ Govt must use more wisely than blindly following the lead of Australia DFA&T hard line stance.