deep wedge
We all know that B42 currently doesn't have MP, but I have a workable solution imo. The scenario is as follows:
2+ players play their single player worlds, but are in a discord call with the other player(s). The players basically roleplay as if they are surviving the event in different parts of the US.
The way the call works is simple, you start out deafened. If you have a working radio on your character, you can undeafen and just mute yourself. Once you get a working walkie talkie or HAM set, you can unmute.
Due to the rather collaborative and timely nature, this does need to be done at the same time, and times do need to be synced up decently (give or take a few hours).