False-Kei immediately collapses, unconscious, on the filthy cobbled alley, rolling into a pool of filthy water.

Gerrard takes on his friend, instead, slashing him with a trio of expertly-aimed swings of his blades. 

The goon, bleeding from several wounds, squints at Gerrard and shakes his head. "You shouldn't have done that."

But as he raises his meaty hand against Gerrard, Boko casts her spell of restraint upon him. DC17 WIS Save: 14

He stiffens, and then topples over like a felled tree, a look of malice frozen on his face. But even paralyzed on the ground, his brow slowly furrows as he tries to break free of Boko's arcane grasp. (His turn: A new DC17 WIS Save: 13 )

...But he remains frozen, his muscles straining to break free of this arcane paralysis.

Everyone may act!

Gerrard:

Moving to Kei, Gerrard carefully rolls him over so he doesn't drown in the puddle--but also doesn't wake up.  "I wouldn't have had to if you hadn't laid hands on my friends," responds Gerrard to the goon, pulling out his recently-used rope so someone can tie him up if they like.

Thwack 

The unnecessary spell fades from Thwack's mind like a drop of dye into a glass of water. "Quick. Quick." He mumbles, obviously impressed at the speed with which the group dispatched their targets. He walks over to Gerrard. "Is keys, Bernard? Kerry wasn't sure. You want me tie up baddies?"

If Gerrard replies in the affirmative,  Thwack will tie up Kei as best he can. (Unmodified roll if needed 7)

Gerrard:

"Not sure," says Gerrard, adding, "Tie up the one who is awake first, if you don't mind." as he indicates the paralyzed goon.  "We need to get somewhere private to have a quiet conversation and figure out for sure if this is Kei," he suggests.

False Kei remains asleep, and will remain so for less than a minute.

His friend continues to mentally struggle against Boko's spell, twitching and trembling on the slimy stones. (He'll get another save momentarily...)

Qivys will help in tying up the two prisoners.  

Thwack has False Kei tied up, albeit not well. (As Qivys helps him, Thwack may reroll his +5 INT(SoH) roll for advantage.) He is still asleep.

The other goon continues to strain against Boko's arcane paralysis. (Qivys will also help Thwack - or anyone else - make a separate INT(SoH) roll at advantage to tie up his buddy, provided...) DC17 WIS Save vs. paralysis: 6

"Yush...yush...yush..." the goon tries to speak but he cannot. He remains paralyzed on the filthy ground of the alley.

Re-roll for advantage 10 

Plus 8 for prof+expertise. 

Quote from See_Ess >>

Re-roll for advantage 10 

Plus 8 for prof+expertise. 

 Qivys works with Thwack to tie the men up.
"I got faith in ya lad!" he tells the kobold.
(giving Bardic Inspiration to Thwack. +1d6 to his roll)

Qivys helps Thwack reinforce the restraints on False-Kei (now a DC18 knot.)

Thwack may make another +5 INT(SoH) roll with advantage, to tie up his buddy.

False-Kei still slumbers, unconscious and securely tied. But his friend continues to struggle against Boko's hold. DC17 WIS Save vs. paralysis: 14

(P.S. Thwack may add Qivys' +1d6 bardic inspiration, too.)

"Should...Should...Should..." babbles False Kei's friend from the cobbles, still firmly bound by Boko's spell.

Thwack 

Surprised by Qivys' help, Thwack moves to tie up the goon. "Th...thanks Kippers." He throws the rope around the goons hands and feet and pulls tightly on the knot.

Int (SoH) roll - 17 plus 3 BI

Gerrard:

”Let’s move them someplace more private before we start a conversation,” suggests Gerrard, picking up the sleeping and bound Kei lookalike.

Both men are securely tied (knot DCs 18 and 19). Both spells are due to wear off momentarily. Gerrard has unconscious (and wet) False-Kei slumped over his shoulder, while his friend remains twitching on the ground.  DC17 WIS Save vs. paralysis: 24

Qivys will grab the other man by one leg and start dragging him along, following Gerrard.
"I could carry ya easy," Qivys tells the man as he drags him. "But ya don't seem ta be tha type that treat other folks gentle like so I want ya ta experience what ya give others." 

Boko moves in to remove any weapons or possessions the goon has on him, and then removes his belt and ties it around his head, covering his eyes. "We do not have to hurt you or anyone this day. We simply seek answers," she says, unsure if either of these two captives recognize the party. Is there anyplace nearby that affords some privacy? Storage container? Rooftop? Garage?

False Kei awakens first, as Boko removes his blade. "What? Who are you? Wait.... You were in the Citadel... I know you... You will pay on so many, many levels..." he rambles.

Boko looks around the alleyway. There are doors and hatches and grated vents leading into the chaotic, lopsided patchwork of neighborhood architecture, but it's difficult to know who or what is inside. The alley is empty of pedestrians at the moment, but you know there are some within a block or so, and more lurking inside.

His friend, dragged across the cobbles, is freed next of his arcane grip. He strains against his bonds. DC19 Strength check: 1