Does griffons and infinity work with traps i have heard that since traps are considered minions that they dont benefit from - light res and + light damage

That's correct they dont work. Griffon is used because its the only option to reach 102 fcr with dual claws. A must in pvp but not in pvm.
Infinity's aura does help though.

https://maxroll.gg/d2/guides/lightning-sentry-assassin

"Traps don't benefit from -% Enemy Lightning Resistance. Using Infinity on your Mercenary is the only effective source for the Lightning Sentry Assassin as Traps are not effected by this Stat on gear. It is only 1/5 effective, reducing monsters to 78% Lightning Resistance."

+4 Damage to each hit
-5 Dexterity
+25% Resist Magic
Fast Attack

vs.

+18 Damage (Raged*)
+25 to Dexterity
+18% Magic Absorb
Indestructible

* - not gonna within Tiger Strike (Daggers)

Blood Body
Magic Plate Mail/Templar Coat/Hellforge Plate
Thul Rune
Perfect Ruby
Any Jewel
+ (1-3) Life Per Demon Kill
(1-3)% Life Stolen Per Hit
+(10-20) To Life

Lesser's Boggi Reciepe. Happy New Year, my friends!