Why won't this datastore work?

Okay. In my game, i use datastores to fill out the values on the leaderboard. I am using an edited version of the Roblox U "Mad Bloxxer" scripts. (No, its not another murder game. I think we've all had enough of those) First off, here's where I first set up my datastores.

function playeradded(player)

    local mydata = datastore:GetAsync(player.userId) or {}
    mydata.wins = mydata.wins or 0
    mydata.BC = mydata.BC or 0
    mydata.hyperlaser = mydata.hyperlaser or 0

    playerdata[player.userId] = mydata


    local leaderstats = Instance.new("Model")
    leaderstats.Name = "leaderstats"
    leaderstats.Parent = player


    local wins = Instance.new("IntValue")
    wins.Name = "Wins"
    wins.Value = mydata.wins
    wins.Parent = leaderstats

    local hyperlaser = Instance.new("IntValue")
    hyperlaser.Name = "Hyperlaser"
    hyperlaser.Value = mydata.hyperlaser
    hyperlaser.Parent = player

    local BC = Instance.new("IntValue")
    BC.Name = "BlitzCreditz"
    BC.Value = mydata.BC
    BC.Parent = leaderstats

    player:WaitForDataReady() -- make sure we aren't looking for leaderstats before they are created
wait(2) -- just in case
local stats2 = player:FindFirstChild("leaderstats"):GetChildren()
for i = 1, #stats2 do
stats2[i].Value = datastore:GetAsync(stats2[i].Name) or 0
end


end
game.Players.PlayerAdded:connect(playeradded)
for _, player in pairs(game.Players:GetPlayers()) do
    playeradded(player)
end 

Here is where I award a win to the player if that player won the game (they won the game if they still have 'MatchTag')

function awardwin(players)
    if type(players) == type({}) then

        for i = 1, #players do
    if players[i]:FindFirstChild("MatchTag") then
            if players[i]:FindFirstChild("leaderstats") then
                if  players[i].leaderstats:FindFirstChild("Wins") then 
                    local stat = players[i].leaderstats.Wins
                    stat.Value = stat.Value + 1
                    local newstat = players[i].leaderstats:FindFirstChild("Wins")
                        local key = "User_" .. players[i].userId
                    datastore:SetAsync(key, function(oldvalue)
                        local newvalue = oldvalue or 0
                        newvalue = newvalue + 1
                    end)
                end
            end
        end
    end
end
end

Heres my variables...

local roundtimer = 90
local intermissiontimer = 5

local datastore = game:GetService("DataStoreService"):GetDataStore("playerdata")
local serverstorage = game:GetService("ServerStorage")
local replicatedstorage = game:GetService("ReplicatedStorage")
local debris = game:GetService("Debris")
local maps = serverstorage:WaitForChild("Maps")
local mapholder = game.Workspace:WaitForChild("MapHolder")
local gear = serverstorage:WaitForChild("Gear")
local statustag = replicatedstorage:WaitForChild("Status")
local timertag = replicatedstorage:WaitForChild("TimerTag")
local Winner = replicatedstorage:WaitForChild("Winner")
local resulttag = replicatedstorage:WaitForChild("result")
local event = replicatedstorage:WaitForChild("RemoteEvent")
local firstrun = true



local playerdata = {}

Finally, here's where its supposed to save the data when the player leaves

    game.Players.PlayerRemoving:connect(function(player)
player:WaitForDataReady() 
wait(1) 
local stats = player:FindFirstChild("leaderstats"):GetChildren()

for i = 1, #stats do
print(stats[i].Name)
datastore:SetAsync(stats[i].Name, stats[i].Value)
end
end)

Thanks for the help! Please just give me an edited script, not some vague answer with an example. Not that I want to be picky, but I am a very novice scripter, and it's very hard to learn from something so vague. If I wanted vague answers, I'd be using the Wiki ;)