I just remembered that Caroline Lucas is on the Industry, Trade, Research, and Energy (ITRE) Committee of the EP. The chair and two of the vice-chairs of this committee have been sent the letter, as have two French Socialist members.
You could include, before the final paragraph, something to this effect:
"Several members of the EP's ITRE Committee, of which you are a member, have been sent a copy of the Open Letter (including the chair and vice-chairs)."
So it's still time to buzz MEPs with the Open Letter, if anyone can do it.