Who should get Def/Res Link 3?

hi friends! so the core of my infantry team consists of boey (idk his ivs but i think -hp +spd) and a +atk -res lukas. they support each other. i use boey as an owl tome user and mainly use lukas's swap or boey's draw back as a means to either have lukas tank or have boey get lukas out of a mage's range while keeping them adjacent to each other.
given these builds, who should i give def/res link to? i have a dancer on the team, so i can buff up to three teammates per turn with def/res link, which is one of the reasons why i'd like this skill.

some things to consider:
1) if i give def/res link to boey, he loses green tome breaker, which will most likely decrease his survivability against other green tome breakers or naturally faster green tome users. at the same time, will the +6 res from def/res link be enough to keep him alive...?
2) if i give def/res link to lukas, he loses qr. i can rectify this with a qr seal, but that replaces close defense. at the same time, def/res link essentially provides the same stat boosts just out of combat as well. if boey has it, lukas can maintain both qr and close defense, raising his defense to up to 59 i think.
pls help!