GOTY Edition should include extra content (namely, the Patient Zero DLC), while still including all the First Season content, so there shouldn't be any issues listing this under the First Season. :)

I couldn't find any other way of listing it

TL;DR version, there's no way to list it on SG to begin with, due to how the GOTY Edition is set up on Steam.

Long version:
Game of the Year Edition only lists in the store as a Bundle, which aren't configured to send information through the Steam API (nor are they allowed to be gifted). Thus, even though keys may be available for the same content as a bundle, nothing is actually listed in the store in a manner that allows it to be referenced through data checks, and there's no way to pull the information SG needs for a giveaway listing through unlisted data.
Meanwhile, manually setting up any kind of data locally on SG is generally avoided due to the high maintanence demands that places on staff, and is never done for any package where there's already a suitable alternative listing available (in this case, First Season) or where a listing may be relisted at a later time. As such, typically only games banned by Valve get their information listed locally on SG.

thanks

thanks!

Thanks!!