I emailed Stephane and got the following response back.
"Good Morning Billy,
I am Ioera from POCHON PRO design office.
On AMEL55, the standard inverter DC/DC is a MAGIC 24/12-20 (MasterVolt).
When this device works in chargins mode (3-step mode) the output charge current is 16A.
This explains the fuse value of 15A.
I stay at your disposal for any further information.
Bureau d’Etude POCHON PRO"