Can i tell if a specific player is playing my game or not?

So i want to get a list of specific players and label whether or not they're playing the game or not. Though i'm worried that due to their privacy settings,

i won't be able to know if they're playing my game or not.

http://wiki.roblox.com/index.php?title=API:Class/TeleportService/GetPlayerPlaceInstanceAsync

Will this be able to detect if a specific player is playing my game regardless of their privacy settings?

thanks

Ok so this meathod uses name for more easyer typing :

local pla = game.Players.LocalPlayer
script.Parent.MouseButton1Click:connect(function() -- this is only requied for button if your not using a button use : game.Players.PlayerAdded:connect(function(plr)
local Item = game.ReplicatedStorage:WaitForChild("DevGun") -- not needed but this is the for item give

if game.Players.LocalPlayer.Name == ("BuilderMan") then
item:Clone().Parent = pla.Backpack -- switch this with what thing you want it to do!
print("yes")
else 
	print("no")

end
end)