What should an employee do who accompanies colleagues on business trips during which they defraud the state by inflating accommodation invoices, and how should he deal with the excess amount paid by the state?

It is not permissible to agree with colleagues to commit forgery in order to unlawfully consume money. One should advise colleagues and state the truth to the employer, provided that reporting does not lead to harm. Money taken unjustly must be returned to its rightful owner; it is not permissible to give it away as charity if it is possible to return it to its owner.