Interesting that you did not succeed negotiating. We had a case where our open-access fund would only help out if the fee was $2000 maximum. We communicated tha

Interesting that you did not succeed negotiating. We had a case where our open-access fund would only help out if the fee was $2000 maximum. We communicated that to the journal and they obliged without further comment. (Though this was after review and that journal really wanted our paper as it was obvious that we would raise their impact factor). I agree that $2000 still seems like a lot of money for an online-only document that journal is not doing anything for aside a little adjusting of the final pdf + paying the editor.