Dc step up

[Jake8]

Hi forum,

A Friend of mine gave me a 3000watt 230VAC (Growatt SPF3000) island inverter with a lion 4kwh battery. I mounted this set into my rv.
This inverter has 2 mppt inputs. To one of these inputs i connected 4pc 420wp solar panels
and on the other input i try to connect the rv's alternator who can supply 14VDC/120A so that the battery charges whils driving even if there is no sunlight.

The mppt requires a 75voc to start (datasheet says 65v but i think that is 65vcc) Now i am trying to boost up the 14vdc alternator voltage to 75vdc in order to feed the mppt with 5amps/375watt, this will draw 30amps at the dc step up IN. Offcourse i dont want to blow up the dc step up's capacitors due to time constant mppt v/s capacitors and also the mosfets becouse of the high current draw.

But maybe i see it wrong and there is a better solution. I was thinking about 2 dc step ups wired parallel to curb the currents.