been threw this about 3 times in the past 2-3 days. It was random at first, now its just constantly not being able to do anything. It happened to me for a like 20-30 minutes at first. Couldnt use any items. Then it was okay, then yesterday i couldnt interact with the server at all. I had all the same problems as you except now it was like i wasn't even connected to the server in the first place. No other characters were there, zombies wouldnt interact, and when i went to look at my ping and desync i realized that they were zero's for everything, including my bandwidth, on the list of players in the server it also showed zero's for all of them. Basically meaning im in the server and able to move about but nothing is registering at all.
I did however conduct a little test. I ran around on the airfield for about 15-20 mins talking on my microphone trying to find another player because i wanted to see if i could die, reset and that would fix it. (i couldnt use the jump or climb and zombies dont attack me so killing myself like that wasn't an option really). I finally had someone say I'm in the jailhouse second floor, so i walked over there went up to the second floor (still unable to interact with doors/items (thankfully all the doors were open) ) . However no one was on the second floor, but i could hear the guy reloading his gun, eating food, and talking to me telling me he was up there. So i walked down the stairs then back up the stairs to see i checked in the entire building couldnt see him, the guy kept insisting he was up there, he couldnt see me either though. Finally i told him i was back upstairs and to just shoot around, next thing i know i finally got the "You are dead" message.
So honestly i have no freaking idea. I couldnt interact with the server, it showed zero's for all my values (ping, bandwidth, ect.) and everyone elses values, however i could hear movements/players talking, and my character was still able to register being killed. So confusing and so annoying, but i guess that's what alphas about, hopefully getting this fixed soon.
To add on to this, i respawned without my flashlight or battery, couldnt do anything again besides run around, thankfully this fixed itself after about 5 mins and i was able to use items and my flashlight and battery appeared in my inventory, however some random kill me like 5 mins after that, i respawned and then i had the same problem with not interacting with the server and was able to do anything, so giving up till this is fixed.