By the time the charger gets the battery to 14.4 volts, amps will have tapered down so there will be little voltage drop.
Standard PD converters do 14.4 not 14.6, so you want a standard PD converter (NOT their LFP model!!!) in the 45 amp range. Make sure it has the Charge Wizard or built in version of that so you can pick and choose between 14.4 and 13.6 yourself.
It is a good idea to have a battery monitor so you can see amps as well as voltage and see AH count so you know where you are at, and not hit the 13.6 button too soon. I have a Renogy 500A one that does the job nicely and is not expensive, eg.
It seems there is no one correct 14.6v that applies to all LFPs, so you are right to look carefully. It is like "AGM" voltage settings that are lower than for Flooded batts--except there are AGMs that specify 14.7v for charging.
However, if Battleborn says to use 14.6 on theirs, I don't know why anybody would choose not to if they have BB LFPs, and use 14.X instead. Up to the individual LFP owner I guess.