"There was no way out. I had a gun at my head," she told the court.
Mrs Oswal said Mr Page told her she could also go to jail over her husband's fraud and the bank's group general counsel Bob Santamaria said her children could end up as orphans.
Mrs Oswal recalled Mr Santamaria as saying: "Both of them will go to jail and the children will become orphans."
Mrs Oswal said during the Sunday meetings her lawyer Grant Pestell said she would not sign the guarantee.
The court heard Mr Page and Mr Oswal were alone in a room at the beginning of the December meetings.
Mrs Oswal said her husband told her Mr Page was very angry and had said: "We must sign the documents. We bloody well sign the documents or there's going to be big trouble."
According to Mrs Oswal, lawyer Darren Greenham said he saw Mr Page with his arm around Mr Oswal's neck, towering over him, but straightened up when the lawyer walked in.
Mrs Oswal said her husband told her he had forged European security documents for loans for their Australian fertiliser business, which operated the Burrup ammonia plant in Western Australia.
Mrs Oswal said Mr Page told her there were people at the bank who believed she was involved all along, which she denied, and she too could go to jail.
She said she knew the personal guarantee with the ANZ, using her 35 per cent stake in parent company Burrup Holdings, was not in her commercial interests but she did in the end sign.
"I had to. There was no other way," she said.
"It was the only way to ensure safety for my husband and to not have receivers in the company and all its associated consequences.
"Pankaj would suffer humiliation. He would lose his business. He would be criminally prosecuted. He'd go to jail."
The Oswals fled Perth in December 2010, after the ANZ demanded the loans be repaid and appointed receivers to the fertiliser business.
Mrs Oswal said she was now completely exposed to the bank and the couple had the same fears as in 2009, including that Mr Oswal could go to jail.
"We left because we were that scared," she said.
The Oswals became well-known in Perth where they owned a vegetarian restaurant chain, luxury cars and Perth homes, including the unfinished "Taj Mahal on the Swan River", a mansion that was to be worth $70 million.
The court has heard the Oswals stripped $150 million out of the Burrup fertiliser business for their own use, including the unfinished mansion.