In some verions of the heter iska contracts, [specifically in the "Heter Iska Bris Pinchas" - see link below] there is a stipulation which states that if the monies received were not directly invested in potentially profit-making venue, the "giver" (the person who gives the money) will receive a share in any potentially profit-making assets which are owned by the receiver of the money.
Thus as long as the party receiving the money owns any type of potentially profit-making assets, the heter iska would still be valid even if the funds were not use3d for a business investment.
HETER ISKA BRIS PINCHAS:
https://www.evernote.com/shard/s502/res/a82e6223-40c4-4438-b11b-e15c5a8af9c9/%D7%A9%D7%98%D7%A8%20%D7%94%D7%99%D7%AA%D7%A8%20%D7%A2%D7%A1%D7%A7%D7%90%20%D7%91%D7%90%D7%A0%D7%92%D7%9C%D7%99%D7%AA%20%282%29%20%281%29.pdf
In some versions of the heter iska contracts, [specifically in the "Heter Iska Bris Pinchas" - see link below] there is a stipulation which states that if the monies received were not directly invested in potentially profit-making venue, the "giver" (the person who gives the money) will receive a share in any potentially profit-making assets which are owned by the receiver of the money.
Thus as long as the party receiving the money owns any type of potentially profit-making assets, the heter iska would still be valid even if the funds were not used for a business investment.
See here for the HETER ISKA BRIS PINCHAS