How do you specify a Flatpak application in .imwheelrc?

Linux Mint 21 Cinnamon
5.15.0-47-generic

I am having some issues with how LibreOffice Calc and Guncash are handling the scroll input from my Logitech M705 mouse. It appears to me that the applications are taking the input and multiplying it. Calc is pretty unusable and Gnucash is just hyper.

I found a bug on the LibreOffice bug tracker. imwheel makes Calc usable with

# Change scroll speed to minimum in LibreOffice Calc
"^libreoffice --calc$"
    None, Up, Button4, 1
    None, Down, Button5, 1

inserted in ~/.imwheelrc (The '1’s are to set one input per click of the wheel. The app does more than that but less than it does unmodified.)

I need to create an entry for GnuCash but it is installed as a Flatpak and

"^gnucash$"

does not work. Nor does

"^org.gnucash.GnuCash$"

. I even tried

"^/usr/bin/flatpak run --branch=stable --arch=x86_64 --command=gnucash --file-forwarding org.gnucash.GnuCash @@ %f @@$" 

(The launch command from the menu.)

Any thoughts on how I can reference the running Flatpak of GnuCash to allow imwheel to work its magic?

I suppose I can go to the deb but it is a slightly older version.

Edit: I also gave

"^org\.gnucash\.GnuCash$"

a shot without success.