Hi
You don't need this device to connect this things together.
I have 2 d8b's with 4 x motu 2408 mk3 and a motu mtp.
You need two apogee sync card.
1 set your daw as master.
2 connect your first d8b sync in on apogee card to sync out on your motu card.
3 set first d8b to word clock in.
4 connect first d8b word clock out to apogee world clock in on d8b 2.
5 set d8b 2 to worldclock in.
Set your d8b's to sync sample rates in options.
REMEMBER to always boot up your d8b's first.
After fully boot start the motu interface.
Good luck