If the organization is reputable they will inform you any time a donation is made in memory of your loved one - if the donor gives them your name and address. There is no need to give you a check (or money in any other form) when it can be sent straight to the organization. When a member of our congregation dies we send a notice to the deceased's family telling them of the donation (but not the amount) and the name of the donor. We send a letter to the donor acknowledging the receipt of the donation and confirming the amount. The donor can use that letter to prove a tax write-off if they choose to do so.

This is my opinion, and that's all it is - an opinion. In my opinion it is bad form to give a check made out to a charitable organization to someone who is grieving the passing of a loved one. If you want to give that person some money to help defray expenses or just to "help them out," that's fine. But if you are donating to a charitable organization in the deceased's memory just send it to the organization. They will inform everyone who needs to know.