What's your firmware version, and what version of lockpick did you use? If you look in your prod.keys file, do you see the "header_key_source"? It's on line 19 in my latest sd card backup.
But also, "
- Nintendo Submission Package (NSP) dumps for both digital and gamecard-based titles."
doesn't have a green check mark next to it, like the other things... so I can't be sure if it works in the rewrite yet. I haven't purchased a new eshop title in forever to even try myself. I will always prefer physical copies when at all possible.
My suggestion for a workaround (assuming you actually have the correct keys), is very time consuming, because you obviously want to use OFW, or at the very least, stock, when getting stuff from the eshop, and under no circumstances should you attempt to use tinfoil on your sys emmc. But... you can backup your current emummc onto PC, then create a new emummc, so that the newly downloaded content will be present on the emummc. Then use tinfoil to dump it. DBI can possibly dump it as well, but I am inexperienced with DBI.
Anyway, after the dump is done, you can restore the emummc that you backed up.