I'm not really sure what you mean by "certified"; I don't think JEDEC are handing out stickers. Although I am reminded of the Bunnie Huang article about SD cards, where the Shenzen vendor would give you the same SD card with the manufacturer logo + holographic authenticity .. of your choice.

The real problem with the RAM business is that it was commodified; normally manufacturers make a relatively small margin. No incentive to build a factory for that. These are not normal times because (a) someone has bought all the RAM and (b) someone has blown up a whole load of globally critical infrastructure in the Middle East.

The risk the existing RAM manufacturers are being cautious about is the risk of normal: if you start building a factory now, will you be selling into a RAM glut?