Fast offering overpayment reimbursement

My Bishop authorized a time-sensitive mortgage payment for a member of our ward and told me the amount. I wrote and sent the check to the mortgage company out of fast offering funds. After that I asked the ward member for their mortgage bill so I could attach it to the expense after the fact. When I got it, I found that the bill was for $50 less than the ward paid.

The Bishop suggested that we have the family make a $50 fast offering donation to reimburse the ward, but this didn't seem like the right solution to me as it would appear as a donation on the family's records. Googling, I see some people suggesting that we have the family make an "anonymous" donation to fast offering. Other people said they can pay using the "Other" category and I transfer it to fast offering.

What's the right way to do this?

gvfarns wrote:What's the right way to do this?

I would place a note from the bishop with the expense stating that the amount paid is a part of the next month's rent, allowing the family to use their own funds to take care of other important needs. The family does not have the $50. The landlord does.

Since I am not the bishop, you might suggest this plan to him and then follow whatever guidance the bishop gives you.