How to allow shortened usernames?

I'm trying to edit the script of a model I've been using for a while. I want the script to be able to detect shortened versions of usernames (So, rather than having to type in "bs joemcburger" I could type "bs joe"

This is the code:

print("Jail") 

jail = script.Parent 

permission = { "joemcburger","burninrubber02","ipwnuFOOLZ"} 


function check(name) 
if table.maxn(permission) == 0 then return true end 
for i = 1,#permission do 
if (string.upper(name) == string.upper(permission[i])) then return true end 
end 
return false 
end 

function Jail(name) 
local player = game.Players:FindFirstChild(name) 
local torso = player.Character:FindFirstChild("Torso") 
if torso == nil then return end 
local location = {jail.Position} 
local i = 1 

local x = location[i].x 
local y = location[i].y 
local z = location[i].z 

x = x + math.random(-1, 1) 
z = z + math.random(-1, 1) 
y = y + math.random(2, 3) 

local cf = torso.CFrame 
local lx = 0 
local ly = y 
local lz = 0 

torso.CFrame = CFrame.new(Vector3.new(x,y,z), Vector3.new(lx,ly,lz)) 
end 

function onChatted(msg, recipient, speaker)

local source = string.lower(speaker.Name)
msg = string.lower(msg) 

if not check(source) then return end 

if string.match(msg, "bs") then  -- Between the brackets, this is what you will say when you want the person teleported. So its like, Person1:jail NUBLET then the nub would teleport to the brick this script is in.
local players=game.Players:GetChildren() 
for i=1, #players do 
if string.match(msg, string.lower(players[i].Name)) then 
Jail(players[i].Name) 
return 
end 
end 
end 
end 

function onPlayerEntered(newPlayer) 
newPlayer.Chatted:connect(function(msg, recipient) onChatted(msg, recipient, newPlayer) end) 
end 

game.Players.ChildAdded:connect(onPlayerEntered)