That OP was talking about nothing on the received lists and that isn't your problem in your post.
Your problem is the delivery man doesn't show up in game. Hence, it was unrelated. There was no need to quote that post.
When that fella mentioned received list, it was referring tho this portion of the UI in PKHeX,
not whatever you're going through.
do you mind showing how your PKHeX setup looks? Based on what you're saying, I am assuming you loaded a PCD and not a PGT.
(Jirachi Gift and Oak's Letter below)
Images that I received both inside.
If you inject PGT's into PKHeX (and I'm using the latest version as of writing), it works.
I literally received them. I think there's no need for my to test if I can receive every card, that is simply asinine.
For starters, show me your PKHeX Mystery Gift UI in your save.
Unless you're editing cards (which at that point you aren't using unmodified cards from us anymore, so you're fully responsible if you muck it up ), there isn't any real need to use those, since PKHeX injects them just fine, as I've demonstrated.
If you are indeed editing the cards, you could always just export the PGT, then import the PGT into PKHeX, if you don't think PMGE loads the cards right.
Also, we have PMGE here, that page has multiple versions uploaded.
Just use a lower version if 1.4.2 isn't there..