JEDEC Initialization (SDRAM)

I have a SAM9G20 with a Micron SDRAM that has been in production for 15 years. The SDRAM is going end of life, and I've been tasked with finding an alternate. Alliance Memory has a "drop in replacement" that I can't get working. While investigating, I found the SDCKE is not being held low. This is part of the JEDEC sequence. Has anyone else ran into similar issues?

Thanks,
