Let me take some time and try and give you at least a somewhat helpful answer.

At the 135 where I cut my teeth on my first jet we had one of “those guys”.
He was already a pain as an FO, came from a Regional where he’d flown a couple of years ( not upgraded) and no doubt he would have been at a Major right now, today, if he hadn’t been such a drama queen.
He got upgraded at the 135 and here we go, almost every diversion and almost every “emergency” and definitely every dire-straits-imminent-demise event.....was this guy.
I upgraded at the same time and flew the same tail numbers in the same geographical areas and in the same weather. Had no drama apart from the normal stuff you deal with as PIC.

Now, having said that.......
Important to note I’m NOT saying you’re a drama llama.
However, you have two strong resume indicators saying that you are. Especially if they take the trouble of calling your previous employers.
135 is a relatively small world and you can count on it your name is tainted.
Most companies are small enough that the DO/Chief pilot still makes the calls themselves.

Solution:
Get into 121.
Large regionals with a revolving door.
They probably won’t call.
Doesn’t mean you’re in the clear.
You can’t lie about your employment and drop one of them off your resume either.

I’ve done some hiring and firing and my attention span is pretty much 3 seconds. So keep my attention.
Don’t go off into the weeds.

Leaving is easier to explain then the firing:

1. “After 3 months I made the decision that this company conducted its operations in an unsafe manner and wanted no further part of it.”
End of story.

2. You’ll need to package this one a little better.
After a frustrating week with weather and cancellations and diversions you had an emergency and following that you had a lapse of judgement and you voiced your frustrations within earshot of customers.
We all know that “pilot-speak” doesn’t translate very well to the non flying public.
You’re very well aware and very sorry about your mistake and you accepted being let go as a result of it.
If you had been the Chief Pilot you would have been forced to do the same.

Now, may I have the job please?

* Something like this ^^^

Now don’t come back here in 9 months after resigning from a Regional.
You need to stay drama free for a couple of years at least.
Good luck.