How to Pack VPK Files into Maps?
Basically what the title says; I'm going to release a map that uses Skotty's energy pellets, but am not sure how to pack the VPK into the map. Please don't hurt me.
VPKs into the maps? I think you are mixing concepts here. what you need is to pack custom models, custom materials and custom sounds maybe into the map before releasing to workshop, right? For this you need pakrat.
There is a nice tutorial at TF2Maps
VPK files are already packed files that store a bunch of files that the game uses....
useful tools and stuff here on TWP 
[spoiler]
[/spoiler]I've already packed the materials/models/sounds, so what is the Valve Developer Community page implying when it says "The VPK file must be included in any map release that contains this port. Otherwise, the energy ball will not work."?
VPKs are an alternate method for providing users custom content. You can't transfer it through the workshop. If you are just adding custom materials, models and sounds you can just pack them the normal way. The VDC page was probably written before the workshop, where you'd only be sending maps as zips and a vpk would be simpler for users to install.
[spoiler]- BEE2 Addons | (BEE2)
- Hammer Addons
Maps:
- Crushed Gel
- Gel is Not Always Helpful[/spoiler]
As TeamSpen210 said, that was an alternate way to make the rest of players be able to "see" the stuff you made your map with. But that sentence you posted doesn't mean what you think it does: "...must be included in any map release..." (not into the map). VPKs used to be distributed altogether with your map and the rest of players should save that .VPK file into a folder named "addons" under portal 2/portal2... But that addons folder is no longer working since the first DLC.
Apart from packing the sounds into the map, you also need to pack the models and materials for those models as I already mentioned in the previous post 
useful tools and stuff here on TWP [spoiler]
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