Q Folder at boot - Issue on the board?

2012 A1278 13" MBP - We get a Q mark folder when we boot up.

The SSD is new & has a fresh Catalina installation which we performed on another unit of the same year so that is confirmed to be working.

I have tried 3 or 4 different connection cables so I am doubting that this is the cause & the cables connector on the board looks to be undamaged in any way (clean). The small 'latch' is also secure (4 minute mark on this video)

Are there any specific data lines or components we should check on the board and if so which ones? @oldturkey03