Download Minecraft Server Resource Package although rejected?

I installed a resource package on the server. Now one was on it and he declined to download it. Can they still download it afterwards?

So,
It could work by deleting its IP from the server's memory. But since that also deletes all of his memory data, it would be bad if he was already making progress.
What you can also do is send him the resource pack as a file, and he'll put it in every time he plays on the server.
The third possibility would be that you open the "Server-resource-packs" folder under "% appdata%" in your ".Minecraft" folder and send him the exact file from your server. But you have to know which it is, because these are text files that are named with a number code instead of a name. He would then only have to pack the file into his same folder and that would have to work.

Here is another screenshot from my folder:

Times have checked whether I can delete the IP. I found the player data folder and also the player. But I think this is the wrong file. After I removed it, the player was still recognized. Do you know which file or folder that is exactly? I'm in via FTP.

He just has to delete the server from his list and add a new one. The setting is in his client, not on your server, so deleting his player.dat does not help.