Transferring NBT via "/data" deleting/skipping information? | SpigotMC | Page 1

Hey! I've made a datapack that mimics the behavior of the keepInventory gamerule, but making it per-player instead of a server-wide gamerule.

However, I'm having an issue in which the NBT data of the Player's Inventory list is getting lost when transferring it to a data storage. This issue is only occurring on Spigot servers and works perfectly fine in vanilla, both singleplayer and multiplayer.

To better explain the issue I'm having;

When the Player dies, it generates a loottable using the method of replacing the default Player death loottable via a datapack and having it redirect to another loottable to generate the following item;

A minecraft:stone_button that copies the NBT of the following directly from the player using the Item Modifier function; minecraft:copy_nbt.

{
  "pools": [
    {
      "rolls": 1,
      "entries": [
        {
          "type": "item",
          "name": "minecraft:stone_button",
          "functions": [
            {
              "function": "minecraft:set_nbt",
              "tag": "{pkiitem:0,inventory:1,Owner:[],Items:[],XpLevel:0,XpP:0.0f}"
            },
            {
              "function": "minecraft:copy_nbt",
              "source": {
                "type": "context",
                "target": "this"
              },
              "ops": [
                {
                  "source": "UUID",
                  "target": "Owner",
                  "op": "replace"
                },
                {
                  "source": "Inventory",
                  "target": "Items",
                  "op": "replace"
                },
                {
                  "source": "XpLevel",
                  "target": "XpLevel",
                  "op": "replace"
                },
                {
                  "source": "XpP",
                  "target": "XpP",
                  "op": "replace"
                }
              ]
            },
            {
              "function": "minecraft:set_count",
              "count": {
                "value": 1,
                "type": "minecraft:constant"
              }
            }
          ]
        }
      ]
    }
  ]
}

To simplify what's happening in the loottable; it creates a minecraft:stone_button and gives it the NBT; {pkiitem:0,inventory:1,Owner:[],Items:[],XpLevel:0,XpP:0.0f}. It then copies the NBT of the Player and puts it with the following;
UUID copied to Owner
Inventory copied to Items
XpLevel copied to XpLevel
XpP copied to XpP

The dropped minecraft:stone_button is then detected by a looping function and preforms the following commands;
(NOTE: The dropped minecraft:stone_button is the "executer".)

data modify storage pki:data hold prepend value {Owner:[],Items:[],XpLevel:0,XpP:0.0f}
data modify storage pki:data hold[0].Owner set from entity @s Item.tag.Owner
data modify storage pki:data hold[0].Items[] set from entity @s Item.tag.Items[]
data modify storage pki:data hold[0].XpLevel set from entity @s Item.tag.XpLevel
data modify storage pki:data hold[0].XpP set from entity @s Item.tag.XpP

It's transfering all the NBT it copied to a data storage, named pki:data. It's putting the gathered data in a listing under hold inside the storage.

Everything copies over properly EXPECT for Items, which is left blank.

I can see where the issue is arising; it's when the NBT from the minecraft:stone_button is copied to pki:data, it basically disappears.

TD;LR

I'm transfering an NBT string from an item to a data storage via a datapack, and it's deleting part of the data. The issue only occurs on Spigot and works perfectly fine in Vanilla, both singleplayer and multiplayer. I'm trying to find what the issue is or if I can use a different method to copy the NBT to prevent the issue.

Important Information
Server Details

Spigot 1.20
Plugins;
floodgae Build#88
geyser build#1453

Datapack

MC 1.20+

#Transferring NBT via "/data" deleting/skipping information?