Gosh, Ryan, this is a tough one.
The long and the short of it is that you need to have a straight-up conversation for your shareholder/s.
Whilst the 40% shareholder may be the minority shareholder, he/she still has a material chunk of the business and finding agreement or common ground during this time is essential.
If you have contributed $140k of capital, then it would be reasonable to expect your fellow shareholders to contribute proportionally. If they cannot, your shares will increase, and their shares will decrease proportionally to the capital you invested.
Or, you could make the loan secured over all of the assets of the company – a (secured shareholder loan), this means at a liquidation event you are paid back first before any surpluses are distributed to the shareholders
The loan and security arrangements would need to be disclosed to the board and recorded in your company’s interest register – check what your companies constitution says about this as it may have certain protocols for you to follow.
This is my opinion – it may help to get a legal perspective.

In the meantime, the Government has been generous in terms of assistance. If you wish to know more about this go to https://www.workandincome.govt.nz/
I’d be more than happy to chat you through these as the 0800 number has a 70 min wait time.