Hi all,
I thought I'd be persistent and see if I could find anything on Barker and Hannah in NZ other than the place they got married. Instead found this document 'Journal by ngairedith'
http://www.familytreecircles.com/passngers-of-the-catherine-stewart-forbes-wellington-1841-32720.html As I read it I realized a couple of things I hadn't noticed before:
1. The very young ages of the passengers.
2. A striking number of families with young 'teenage' girls and boys.
3. A person by the name of Mary Durham who in this document is described as a MATRON.
4. The fact that Hannah wasn't the only very young semptress.
Others seemingly travelling on their own are:
Amoss, Mary Ann - 19 - Dressmaker
Squire, Emma - 16 – Sempstress
Swaffer, Martha - 22 - Sempstress
Swaffer, Matilda - 19 - Sempstress
Many other girls in the families use the same title 'semptress' to describe their skills - one as young as 12 years of age.
I then thought that if you add Matron Durham who is 54 years of age (the oldest passenger) and at minimum five girls all calling themselves 'semptresses' could it be that they all 'belong together'

Maybe it's grasping at straws but a bunch of girls being allowed to go abroad under the patronage??? of an older woman seems a far more likely scenario than all these young ladies travelling on their own???
It doesn't rule out the possibility that Barker and Hannah eloped, but perhaps this is an avenue to set about discovering.
Cheers barkrels