Is the money you obtained through your manager submitting invoices that do not match the disbursed amounts considered unlawful (haram) or dubious (فيه شبهة)? And how should you deal with it?

What your manager did—submitting a food bill that you both did not fully pay to the company, making it seem as if it was fully paid to receive its entire value—is an act of deception and unlawfully consuming wealth. This is based on the Almighty's saying: "Indeed, Allah commands you to render trusts to whom they are due," and the Prophet's (peace be upon him) saying: "Whoever deceives is not of us." It is not permissible for you to partake in this sin by accepting a portion of this ill-gotten money. The obligation is to return the money exceeding the bill's value to the company, or to seek forgiveness from the company owner or the authorized person in charge.