The custom cooler makes sense (though it doesn't show if it's flat, I assume it is if the memory needs pads). But I am surprised they wouldn't try to use an existing mount holes pattern like the Socket SP5 for Epyc/TR that is 90mm x 90mm
unfortunately it's not flat... here you can see this from how the black LEXAN insulator is applied

here you can see it better... memory and VRM cooling surfaces sitting lower than the contact area for the die


so even if they had adapted a standard mounting pattern, it would still require quite some modding for us to use another cooler