you can also donate via the Free software foundation, I'm not sure what the author prefers, but the FSF donation can most likely be matched 100% if your company participates in a matching program.

Hopefully, adding a "for 'GNU Octave' project" note should be enough.

There's a specific donation page for Octave.

https://my.fsf.org/donate/working-together/octave

Using the regular donation page with a note will just complicate the lives of the FSF staff.

Thanks for posting this link davexunit. Just donated $100. I used Octave in undergrad for some engineering classes. This doesn't solve the long term problem for the author but I hope it provides some temporary relief.