Why isn't model isn't regenerating after a person leaves the game?

Is there any way to fix this script so that the 'local backup' is removed once the 'backup.Main.Owner.Value' becomes empty? I'm thinking I need some way of checking whether the Owner of the tycoon is still in the game and then to regenerate after they leave but I don't know how I would go about this without lagging up the game.

wait(1)
local model = game.ReplicatedStorage.Tycoon1
local floor = script.Parent.Floor
local backup = model:Clone()
backup.Parent = game.Workspace
backup.PrimaryPart = backup.Baseplate
wait(0.1)
backup:SetPrimaryPartCFrame(CFrame.new(floor.Position))

local function Regen() 
    backup:Destroy()
    wait(1) 
    backup = backup:Clone()
    backup.Parent = script.Parent  
    backup:MakeJoints()
end

while true do 
    wait(1.5) 

    if backup.Main.Owner.Value ~= "" then 
        if not game.Players:FindFirstChild(backup.Main.Owner.Value) then 
            Regen() 

        end 
    end 
end 

Any and all help is appreciated!