Your organization may have some contractual remedies against the borrower. The mortgage or note may require the borrower to maintain the property in good condition and may prohibit the borrower from removing improvements from the property (for example, in Section 7 of the Fannie Mae and Freddie Mac Uniform Security Instruments for Illinois).
As to criminal law, there may be a crime that would apply here, but it is highly unlikely that a states attorney would be willing to prosecute the borrower in this situation. The Illinois Criminal Code does provide for a specific crime of “concealment of collateral” that may apply in this situation. (This offense was added to the Criminal Code as part of the IBA’s “Illinois Financial Crime Law” in 2003.) This law makes it a crime when anyone “with intent to defraud, knowingly conceals, removes, disposes of, or converts to the person’s own use or to that of another any property mortgaged or pledged to or held by a financial institution.” 720 ILCS 5/17-10.6(e). If the borrower removed property from a home that was mortgaged to your financial institution, this law may apply.