Oh no… Out of their lineup of long chassis this one is specifically the only to not fit EE-ATX motherboard. It would have been very good fit!
It’s 1.68" taller than normal SSI-EEB (13.68" x 13.00"):
Red line show where normal SSI-EEB board (and E-ATX/ATX) end.
That additional bit above I/O shield destroys compatibility with most of rack-mountable chassis and everything with top-mounted stuff.
Welp, I knew I was getting into though battle with them, but I need the RAM capacity.