Swapped out buttons but broke black latch on FFC connector

The first image is the button ribbon and connector, missing the black latch. The second image shows what the black latch should look like (from the d pad cable side).

When I start up the SteamDeck, the buttons arent recognized and do nothing. I only assume its because the latch thats supposed to be there, isnt.

My question to the SteamDeck gurus are:

1. Should the buttons still actuate with the cable slid in as showing, or is the black latch integral to making it work? I understand that the latch keeps it firmly in place, but if the buttons arent working, is that instead a sign of other issues?
2. Would ordering a new connector and cannabilizing its black latch, fix this problem?
3. Has anyone had to do this sort of thing before?
4. Do you know exactly what this part is called? I assume ifixit, amazon or aliexpress would have the part needed, just dont want to order the wrong thing.
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