I personally see no benefit in LECI for your scenario, at least you would add a lot organisation steps around it.
I also see no need to add a high effort to control if somebody did a receipt or not, this will usually automatically come to the surface, either because the vendor is complaining that he does not get the money, or because he gets a dunning letter for late delivery, or somebody wants post a goods issue and there is no quantity in SAP.
Looking around for gate pass I came across a book which tells about gate pass and Challan (but this did not really get me closer to the subject and also not to match it with your scenario): https://books.google.de/books?id=gpNQCwAAQBAJ&pg=PA60&lpg=PA60&dq=gate+pass+challan&source=bl&ots=9EfixjESiV&sig=Ps4xXwv…
And there is also a document with screenshots, but the user who made it did probably not know that Z-transactions are own-developed transactions.