https://airvpn.org/mission/ and https://www.eff.org/thanks
AirVPN's own page states being a "Super Major Donor (2500 $/year; recurring)". As far as I can tell they've changed it recently and these are now considered "legacy" thanks (sounds weird I know) but it'd have put AirVPN on a reputable bracket with not too many companies there: "Innovator Level ($2,500)"
I've done some digging at it appears there must have been two separate systems for EFF donations:
The regular donation page (that used to list names and specifically Super Major Donor)
A Separate donation for companies that will end up on this honorary thanks page
From this digging on the Internet Archive I also got that AirVPN has been (according to own website) donating to EFF for a very long time but failed capitalize on this opportunity to be included on the list. Meanwhile some other companies/names have been contributing the bare minimum (Leader Level ($1,000) to be included on that page.
I thought to bring this to your attention.