I was able to reproduce the problem (same error messages) on an Asus Eee PC X101CH which has an Intel Atom N2600 CPU that supports EMT64 by default, but Asus disabled this in the BIOS, so I tried the latest x86 build for Recalbox 6 and it crashed just like it was described in this thread.

(Luckily, I was able to find a BIOS mod which re-enabled EMT64 support and after that I was able to boot the x64 version of Recalbox 6 on the very same device.)