There will be no WiFi at PanSIG 2020.
You may want to look into renting WiFi during the weekend.
If you are a presenter, it is recommended that you save a copy of you presentation on you device, complete with audio/video clips, just in case the WiFi is slow or experiences issues. If you intend to play media from the internet, please make your own arrangements for connectivity (phone tethering, wifi hotspot). (There's more information for presenters on this site.)