So since it worked before adding this world, it's obvious to both of us that the issue is with the world, and not your server setup. Have you gone to the creator's Discord and asked for support? You're a paying customer, so they should be willing to help, to avoid a return or bad review. That's probably what I would do in this situation.
icon AdvancedEnchantments-9.14.5.jar JAR File 3.41 MB Dec 30 03:02 icon AdvancedPets-2.15.5.jar JAR File 4.06 MB Dec 30 03:02 icon AuraSkills-2.2.4.jar JAR File 4.03 MB Jan 02 20:43 icon BankPlus-6.4-alpha2.jar JAR File 365.98 KB Jan 02 20:41 Edit icon ChatControl-11.0.7-BETA.jar JAR File 4.8 MB Jan 07 20:10 icon ChatGames-2.1.8.jar JAR File 102.35 KB Jan 02 20:41 Edit icon DecentHolograms-2.8.12.jar JAR File 1015.79 KB Dec 30 03:02 icon DeluxeTags-1.8.3-DEV-23.jar JAR File 374 KB Jan 02 20:41 Edit icon EconomyShopGUI-6.10.1.jar JAR File 1.33 MB Dec 30 03:02 icon EssentialsX-2.20.1.jar JAR File 2.93 MB Dec 30 03:02 icon EssentialsXChat-2.20.1.jar JAR File 17.41 KB Dec 30 03:02 Edit icon EssentialsXSpawn-2.20.1.jar JAR File 17.7 KB Dec 30 03:02 Edit icon Fadah-Bukkit-2.7.4.jar JAR File 763.61 KB Dec 30 05:48 icon FancyNpcs-2.4.1.jar JAR File 2.18 MB Jan 10 21:06 icon FastAsyncWorldEdit-Paper-2.12.3.jar JAR File 15.12 MB Jan 10 21:53 icon Geyser-Spigot.jar JAR File 20.94 MB Jan 08 17:20 icon Geyser-ViaProxy.jar JAR File 20.17 MB Jan 08 17:20 icon LuckPerms-Bukkit-5.4.150.jar JAR File 1.4 MB Dec 30 03:02 icon LuckyPouches.jar JAR File 897.19 KB Jan 07 20:10 icon ODailyQuests-2.3.0-SNAPSHOT-15.jar JAR File 365.95 KB Jan 02 20:43 Edit icon PhoenixCratesLite-3.7.6.jar JAR File 3.64 MB Dec 31 00:15 icon PlaceholderAPI-2.11.6.jar JAR File 911.26 KB Jan 05 01:58 icon PlayerBounties-1.5.4.jar JAR File 265.26 KB Jan 02 20:42 Edit icon ProtocolLib.jar JAR File 5.13 MB Dec 30 03:12 icon Quests-3.15.2-b216e2b.jar JAR File 959.58 KB Jan 02 20:42 icon SuperiorSkyblock2-2024.4.jar JAR File 4.74 MB Dec 30 01:18 icon TAB v5.0.3.jar JAR File 1.31 MB Jan 07 01:00 icon Vault.jar JAR File 265.88 KB Dec 30 03:12 Edit icon ViaBackwards-5.2.1.jar JAR File 1.16 MB Jan 10 21:06 icon ViaVersion-5.2.0.jar JAR File 4.76 MB Dec 30 00:01 icon ViaVersion-5.2.1.jar JAR File 4.76 MB Jan 08 17:39 icon VotifierPlus.jar JAR File 238.55 KB Jan 10 21:06 Edit icon VotingPlugin-6.18.jar JAR File 3.57 MB Jan 10 21:06 icon Vouchers - v3.26.0.jar JAR File 1.77 MB Jan 04 05:06 icon WildStacker-2024.4.jar JAR File 1.38 MB Dec 30 05:48 icon bank-plugin-lite-latest-all.jar JAR File 414.43 KB Jan 02 20:41 Edit icon core-latest.jar JAR File 712.01 KB Jan 02 20:45 icon floodgate-spigot.jar JAR File 11 MB Jan 08 17:23 icon hypewelcome-1.0.0.jar JAR File 155.11 KB Jan 02 20:42 Edit icon item-nbt-api-plugin-2.14.1.jar JAR File 234.38 KB Jan 03 04:48 Edit icon nightcore-2.7.3.jar JAR File 605.94 KB Dec 30 19:55 icon playershop.jar JAR File 60.05 KB Dec 30 05:48 Edit icon voidchest-5.2.0-downgraded.jar JAR File 2.1 MB Jan 07 03:59 icon worldedit-bukkit-7.3.9.jar JAR File 5.83 MB Dec 29 23:59 icon worldguard-bukkit-7.0.12-dist.jar
yeah, it's gotta be a plugin at this point. I'm just confused, because he said it worked with his first world, and now hasn't worked since. so there's some level of persistence somewhere outside the world folder that is preventing a successful new world from being used.