A player got upset because he made a wrong move and now I can’t DM

So I’m running an Agents of SHIELD campaign per my group’s request because the other DMs in my group needed a break running during COVID. I gladly picked it up even though I’m not a super experienced DM and I gave everyone pretty powerful characters since they’re supposed to be heroes.

One of the players, we’ll call him Chris, is an extremely experienced DM and player and was very helpful in getting the custom mechanics running for the game. The first two sessions went great, they uncovered the story points they needed, there weren’t a ton of issues aside from everyone rolling pretty badly (which is a consistent issue since we were using roll20). Chris even rolled 5 nat 1s in just the first session. My NPCs weren’t designed to cause a lot of damage, but they were more of an obstacle with one pretty tough baddie that was supposed to be able to at least be a threat. Well it turned out that about 1 in every 5 hits NPCs made landed because of the rolling.

Cut to session 3, I let the players choose their mission and it lead them to a factory where they all had awful rolls and I had to help them out quite a bit and give them more opportunities to find the information they wanted, which lead them to an individual who was missing, which took them to his house. Inside the house was a robot that didn’t stand a chance against them. Cut to more botched NPC rolls and he’s dead. They find a bomb in the robot, roll high to disarm it, no longer an issue. Then they found a computer that was trapped to wipe the memory if someone tried hacking it. One character has something crazy like a +16 computer use check, so it shouldn’t have been a problem. He rolled a nat 1.

Chris said out of game, "Well if we unplug it, then it’ll stop the memory wipe." I allowed it because the computer had vital information. I let the character roll a Reflex save (which again should have been high) and even with an action due he rolled pretty low. After they found most of the information, I warned them that the police were coming (in this world, SHIELD isn’t an official government entity and is technically working illegally, but some places let them do their job while others will prosecute without questions).

Everyone but Chris wanted to take the evidence and run. Chris was adamant on talking to the police and for some reason the other players let it happen without arguing. So the police get there, I let Chris roll his crazy high Diplomacy and let them know that his roll is keeping them from being arrested. It was at that point that Chris tried playing the "I’m an agent of Shield" card. Before I could correct him, the other players told him that SHIELD doesn’t actually have authority. Apparently he was the only one who didn’t read the back story. OK, it happens. I wasn’t mad. Until he continued to try to pull rank on the police and antagonize them. I kept reminding him that he doesn’t have a rank. Then the police chief (who was corrupt and a major part of their story line) shows up. I made it VERY clear that this guy didn’t like them. I very heavily hinted through what he said that he didn’t want them anywhere near the case. Chris even pointed out the flaws in how the character was acting.

And this is where I messed up. Because he kept beating around the fact that the chief was acting weird, I let the scene go on too long when I probably should have forced a sense motive check. This caused Chris to start antagonizing more and more, and then he essentially asked him to hand over the evidence after being told that they weren’t allowed to be a part of the case. He was told no, flat out. Chris then blamed another character, which caused both of them to sign off immediately.

The next day Chris messaged me telling me that I was taking my frustrations out on the players because I was rolling badly and that’s why him and the other player quit early. I told him exactly what happened and why, that the police chief was corrupt and no matter how high he rolled on Diplomacy that he wasn’t just going to GIVE the evidence over. Then he tried to say that I was being insensitive because "even though it’s more realistic, having a cop in front of your character and not being able to do anything about the situation is too topical. That’s why me and (the other player) left".

Then I made my next mistake and told him that the other guy left because Chris was blaming him for everything when it was really Chris’ fault for antagonizing an NPC who already didn’t like him.

Now, my group is struggling to get a game going because all of the DM’s are pissed. I told everyone my game is on pause because if a corrupt cop is too much for someone then the rest of the storyline definitely won’t work. I spoke with everyone individually and everyone else agreed that Chris was the problem. But now I don’t know what to do to get everyone back on track.

The other players have defended him by saying he is under stress. That’s fine, we all are, I didn’t think anything of it. I’m not looking so much for advice on what happened, but where to go from here and how to get the group back into gaming. The other players also said they didn’t feel like anything was wrong with the campaign or story. But I’m also the newer person in the group, so I’m not sure if they want to game without Chris.

Requested TLDR: one of the experienced players is keeping the whole group from gaming, what can I do to get us back on track. Do I need to talk to him again before asking everyone if we should kick him out

We’re playing modified 3.5