The MSI QVL you provided in the link already has support for 64GB kits. I think the way they presented the information can be misleading. The “Size” refers to the size of a single module (stick) and “1|2|4 DIMM” refers to how many sticks they have verified the XMP to work.

So if you’re interested in 64GB 2 stick kits, you have to look at “Size” of 32GB and “1|2|4 DIMM” of √ | √ | .