Is it permissible to agree with the bank to cover guarantee checks with usurious interest to avoid the issuance of a "insufficient funds" document, knowing that the supplier might use the check for leverage?

Borrowing with interest is forbidden by scholarly consensus. Its prohibition is supported by religious texts, including the Almighty's saying: "O you who have believed, fear Allah and give up what remains [due to you] of interest, if you should be believers. And if you do not, then be informed of a war [against you] from Allah and His Messenger." And what Muslim narrated from Jabir: "The Messenger of Allah cursed the one who consumes Riba (interest), the one who pays it, the one who writes it down, and the two who witness it. And he said: 'They are all equal (in sin).'" And the Prophet's (PBUH) saying: "Riba (interest) has seventy-three doors, the easiest of which is like a man committing incest with his mother."

It is not permissible to engage in Riba (interest) except out of necessity. The limit of necessity is when one predominantly believes that they will perish, or suffer unbearable hardship, or be unable to achieve the minimum standard of living for the poor. Necessity—if proven—is estimated according to its extent. Once the necessity ceases or a viable alternative is found, dealing with Riba becomes impermissible, and the matter reverts to its original state of absolute prohibition. Presenting checks before their due date is not permissible.