"It's overwhelming for me and I'm pretty sure it's going to be overwhelming at the other end," she told Fairfax.
"There's nothing that's come through of any real confirmation, there are a couple of possibilities, but I just need to know that these people were in Queenstown at that time."
The post has been shared more than 14,000 times and has attracted hundreds of comments -- the majority of which are positive.
In it, Kerryn Leigh wrote: "We want nothing from him but possible conversation. Who knows, I just need to do this for her."
She described Rodney as a surfer living on the Gold Coast with long scruffy hair, blue eyes and is believed to be in his late 40s now.