

Time to update the resume.
If you’re already on shaky terms, this mess could be pinned on you and you’ll be out the door before you get a chance to pull up the paper trail leading to your boss.
In a less drop everything and run scenario, Is this feature a physical add-on or something done via software. Could always dig the hole deeper to stall for time and say parts are on backorder or someone key to implementing the feature is on sudden bereavement leave.
Well there’s your ticket out “we’re sorry the manufacture has discontinued this feature, here’s a new solution”.
Also its 100% better if the clients finds out the feature is missing via your company. A good company will make it right, ideally by adding the feature retroactively at no cost. If it can’t be added, open the checkbooks and refund the difference or find a new solution at a reduced cost (quote the new stuff, but not the replacements).
Sounds like it’s above your paygrade, if the company loses the client that’s not on you (even though they can still blame you)