ive got a r15 ship but its an engineer the highest fighter i got is r10 full syngery,
so when i read this for me it translate to: do 3 matches, use fighter, the highest one u have (im using the lance).
apparently its not the case i ask for help on the chat, but all i get is not helpful responses 
If you have a r15 engi in a faction as a max rank ship then you have to have r15 fighter as well, otherwise it doesnt count. You can try some other fighter in other factions if you havent reached r15 in them to finish the mission.
1 hour ago, ORCA1911 said:
If you have a r15 engi in a faction as a max rank ship then you have to have r15 fighter as well, otherwise it doesnt count. You can try some other fighter in other factions if you havent reached r15 in them to finish the mission.
Nope. The only requirement is to have highest ranked ship of any faction in slot (any slot) while flying a fighter. However there is another issue - if OP has R15 in all 4 factions, then the fighter has to be R12 or higher, otherwise MM will not allow him to use that ship (with the exception of PvE - then it will be R11 or higher).
OP has ranks 15 15 15 5 and his only fighter is R10 Lance. I would strongly suggest to craft one Ellydium ship and put it in slot. That way you can do this task even with R5 fighter.
I have it all on 15 so all i know about that max rank thing was when i had a r5 tharga, easy progress but idk if you can do it still, just sayan.