Cash on delivery with fee + splitted orders

[Bocco]

Hi. 

I am using Cash on delivery with fee (Sakis Gkiokas). Module works like a charm. 

But now I am trying to get fee with splitted orders - using different carriers. I don't know how to do this. As soon products in cart use different carriers, I get fee 0. 

Does anybody know how to get fee in this case?

I was trying to get info from author Sakis Gkiokas, but I think his post with his module is deleted in prestashop forum, so I can't contact him. 

[idnovate.com]

If interested, with our module https://www.idnovate.com/en/1370-cash-on-delivery-with-fee-surcharge-plus-cod.html the fee is applied only to one of the splitted orders.