@lalarabbit (and everybody), following some updates we’ve had other users successfully configure access to OpenAthens (manually via library Settings > Proxy Access) with a link resolver looking like:
https://go.openathens.net/redirector/qut.edu.au?url=$@
You would need to replace the qut.edu.au bit with your own institution’s URL (or something like that). The most important thing is making sure to include ?url=$@ or /login?url=$@ at the end of the link. Anybody who’s able to try this with their institutional login, please let us know if it works.