That’s not how it works, it’s a limited company that is publicly traded. The company is its own person and it owns the debt.
He owns 30% of the shares, the shareholders are investors who give money for a share of the business and a return on their investment. The shareholders are the last people to be paid, they should get the highest return over most other forms of capital but it also comes with the highest risk. If there are any problems you get nothing or if the business performs poorly your investment is worth less. You can only normally get your investment out by selling it to someone else. The business doesn’t owe any money to shareholders and they are also not liable for any debt (hence limited liability).
Once a company is wound up any money left over is shared between shareholders after all other creditors have been paid. Trading companies only normally get wound up when their liabilities are greater than their assets (insolvent) and this after administrators have been paid there is normally nothing left.
Most investors have few shares in lots of companies to mitigate against the risk.
Creditors are people who the business owns money to, this can be a loan, overdraft, money owed for stock, tax bill etc. Creditors are higher up the food chain than shareholders.