Good to hear from you and great photos the mate. Here in Sydney we are sweltering in some parts 40c+ so its quite funny to see the other extreme.
Thanks for posting, as for your result, thats why they call it fishing, not catching
Yes, Sweep or Silver Sweep.
Just to remove doubt, if someone gets a funny looking Sweep, you do occasionally get Sea Sweep in Sydney but far from common.
So Sweep it is Scorpis lineolata
Pretty sure its a Spangled Emperor. (Juvenile) Lethrinus nebulosus.
Grassys don't have the amount of Blue spot or the blue lines coming down from the eyes.
Yes your right, I assume you have pointed out to them to look this up on the RMS sight.
When they realise their mistake they should give you a big discount and invite you back explaining how wrong they were and how right you were.