Yes, he was saying "ore", which is an incredibly rude and amateur mistake. In English, that would be like be entering an important business meeting with a bank and saying, "Yo dude, wassup?"
Depends on whether I can make sense of the *nix joke on the banker’s t-shirt, or if I can tell how many months of salary his tie is worth.
I thought it depends on how many zeroes you have at the end of your (positive) account balance with the bank.
Are you sure he was saying "ore"? Given the fact that his grammar is otherwise pretty tight, I wouldn't be surprised if he were instead using "ware".
Grammar & honorifics/formality are two separate subjects. I'm not fluent in Japanese by any stretch of the imagination, but I know the basics of grammar while I know basically nothing about formal speech/informal speech.