It can help to summon the ogres if you have the horn. They soak up some of the heavy attacks that would otherwise be going to your party.
Disarming the githyanki helps. Sarth isn't much without a greatsword.
Maybe wear the minotaur's amulet, the one that gives resistance to slashing damage at the cost of a vulnerability to bludgeoning. Since none of the gith are using blunt weapons, there's no drawback to the item in this fight. And it will give some resistance.
Use your potions when you can in the fight. An invisibility potion, even after the fight starts, can save the day. A void bulb can pull together several of the gith if you want to get them in a group for something like a cloud of daggers.
Disarming is an ability that comes from the Battlemaster maneuvers right? Or are there other options? As Lae'zel is an Eldritch Knight, in retrospect a questionable choice, but I also found it thematically fitting due to her race.
As for the amulet, didn't consider that one, but that might actually be an interesting choice. That being said, in this case, I feel that, storywise speaking, the Underdark comes after beating the Githyanki Patrol as, Will argue's that when having killed the goblin leaders, you should finally pursue Lae'zel her option. I'm not sure what comes first, logically speaking, but I think both area's sport level 5 creatures, so it's up for debate I guess.
The cloud of daggers is a spell I never picked, because the name alone really felt thematically more befitting an Arcane Trickster, yet sadly, choosing that spell so far, isn't an option, so I ended up never adding it to my Wizard.
