No problems Carl you can imagine we get a lot of wind ups on here you would be surprised!
I can see you both have been through an ordeal with the car and surprised you didn't chuck in the towel by now.
The issue I have is money and time. The facts are whatever the ropie mechanics' has done or not done properly, we can't determine if he has missed a few steps or cut corners that fundamentally have ruined a salvageable engine.
If your new mechanic is competent and you trust him he should be able to determine what’s gone wrong.
But if you were to be based in UK definitely think a second hand engine would be the quickest and cheapest option available.
I have an old friend in New Zealand I might PM you his email, because he loves his cars and it’s a small community over there. I wouldn't feel comfortable unless I had seen the internal of the bores to establish essentially whether to chuck in the towel.
If you have specific questions I'm sure other members on here will provide help to you if needed.
I think if you had done some of the work and have a good general mechanical knowledge it would be easier if you get what you need, but trying to second guess any mechanics you have hired with our knowledge might help a bit, but in reality could hamper the fixing process.
Owning a MK2 golf is emotional and half of us feel that pain at some point of ownership.
Anyway let’s see if anyone can offer more help as we know a bit more about you!
Enjoy your stay and the search button is really helpful as is the maintenance section I’ve linked both functions for you bellow!

Jay
http://www.golfgtiforum.co.uk/index.php?board=40.0http://www.golfgtiforum.co.uk/index.php?action=search;advancedPS introduce yourself in the welcome section found here the more people who know why you are on here might be able to help aswell as I think we have some NZ members on here that they can put you intouch with aswell!
http://www.golfgtiforum.co.uk/index.php?board=29.0