XBEE3 802.15.4 Fails running SPI with FW 2012 and FW 200D

We are trying to connect a XBEE 3 module with a FPGA and encountered following behavior :

With TH module FW 200C (firmware compatibility = 1): we could have SPI running (boot message, AT commands, RF packet received, …)
With same TH module (same wiring) FW 2012 : SPI is not working, ATTN never asserts. If DOUT is driven low, the module does not even boot properly
With a micromodule FW 200D (firmware compatibility = 2) : ATTN asserts after 5ms but never return data on MISO … and never de-asserts.
With same micromodule FW 2012 : ATTN never asserts… Even after sending commands of bunch of xFF with CLK…
The thing is that we could only find some recent modules on the market with firmware compatibility = 2.
Did any one ever faced that kind of issue?

Thanks for your support,

This is something you should report to Digi Technical Support by going to my.digi.com, logging in and submitting a case.

Please confirm the frequency of the spi protocol within band 4Mhz between 5Mhz.