Jalt points to the area where he saw the lizard folk's heads pop up and he casts Guardian of Faith in that location. He then proceeds to start making his way across the bridge. 

Is Jalt travelling at:
1. Normal speed?
2. Slowly and carefully?
3. Running quickly?

17

He's moving slowly across the bridge

Jalt, you see your guardian up ahead, floating slightly above the ground.  You see no evidence of any attackers.

Tangle is up.

Tangle nocks an arrow and draws to her cheek, sighting across the bridge at the stairs. She readies to fire if any lizard head should pop up.

Move: zero, holding steady for aim.
Bonus Action: Steady Aim for Advantage on her "next attack roll on the current turn."
Action: Ready a shot for if a lizardfolk appears. That shot will be with Advantage, and thus with Sneak damage, if I read the rules correctly? I will roll for that Readied shot in case it happens, so you don't have to come back to me. 22 to hit, for 20 piercing dmg.
Reaction: To be used to take the Readied shot, if the opportunity presents itself.

Bazavur is up.

Bazavur begins crawling his way across the bridge. Not wanting to risk falling again. 

Give me a DEX save with advantage.

Dex save: 6

Bazavur goes tumbling towards the sides again.  Give me an Acrobatics check.

Acrobatics check: 23

Bazavur, you reach out and grasp the side of the bridge.  You find yourself in a very familiar situation, hanging over the edge, snarling and chomping noises coming from down below.

You hear a grunt of pain coming from the other side of the bridge.  DEX save:  18 minus 1.  You hear sounds of movement, but it's not clear what is happening.

Soar is up.

“I hate this bridge!” Bazavur declares as he slips towards the edge and manages to grab it to keep himself from falling again. 

Soar tries to loop the rope around Bazavur again, more securely, whatever she can get hold of. Not tying, just something he could grab hold of and use to get himself to safety. "Let's get you back up safe, or you're going to convince me you just want to fall down and explore that pit alone. No more bridge crossing without a rope, mister!" 

If that takes an action, she'll use an action. If not, she'll ready an eldritch blast for any enemy down the way.

It's a free action to give Bazavur the rope, and a full action to lift him up.  It's a little easier now that you're doing it in the same conditions for the same time.

Bazavur, you are standing on the bridge.

If the lizardfolk are doing something, it's outside your line of sight.  You all do see Jalt's guardian keeping watch on the other side of the bridge.

Round Three:
LF3
Jalt
Tangle
Bazavur
LF2
Soar
LF4

Jalt is up.

Jalt having heard a slight cry casts Spiritual Weapon at 3rd lvl with his bonus action and places it close to where he heard the noise. With his action, Jalt will cast Light on the Staff of Healing and starts walking more along the bridge towards the other side. 

17

Carefully across the bridge 

Jalt, you advance slowly and carefully, your light spell illuminating the area and drawing several hisses from down below.

As you get to the middle of the bridge, you are able to see a little better down the opposite side's staircase.  You see a yuan-ti and a badly-hurt lizardfolk standing just beyond the reach of your Guardian of Faith.  If there's anything beyond them, you cannot see it.

SW attack on the Lizardfolk: Attack: 13 Damage: Unable to parse dice roll.