Of course, the real problem would be explaining to the general population that this works. Great in theory, but will never pan out
Show me your receipt saying you voted for Big Ron and I’ll give you a fiver and/or won’t hit you in the knees with a spanner.
It’s not a perfect system, but I would personally find it comforting knowing that I could verify that my vote counted and that I could independently confirm the election results
Edit: haven’t read the paper in a while, but IIRC you can see that the vote counted without revealing details of who you voted for. They definitely would have covered this case
You can take a picture of a marked paper ballot, trade it in for a fresh one (original is destroyed) and mark the new one differently and turn it in.
A ballot picture doesn't prove the ballot was cast and counted, a receipt that identifies the voted candidate does.
That said, check the edit. This case is definitely covered, I just forgot