Is money acquired from selling company products through fraudulent means considered permissible, especially after the regional sales manager claimed that the general manager had forgiven the sales team? And is it permissible to borrow from this money for trade with the intention of repaying the debt later?

What the delegates did by claiming to sell to the hospital and then selling the product in the market at double the price and taking the difference for themselves is a forbidden act that involves lying, forgery, betrayal of trust, and consuming wealth unlawfully. They must repent and return the money to the company. If the General Manager is the owner of the company and forgave the money, then you are not obliged to return it. But if he is not the owner, then his forgiveness is not valid. You are obliged to return the money to the company if you are not certain that its owner has forgiven it. You must sell the lands to repay their price, and whatever remains will be a debt upon you. It is not permissible for you to borrow from it or trade with it, because repayment must be immediate, for the Prophet (peace and blessings of Allah be upon him) said: "On the hand is what it took until it returns it."