WRT to Some saying Flynn lied about the transcript while others say he didn't; That could very well be a Canary Trap Flynn set up and different copies of the call transcript were sent out.
Obama removing Russian diplomats may have been designed for the purpose of making sure Flynn engaged with the Russians. Flynn aksed and got permission from the Obama WH to talk to the Russians, I believe, in his capacity on the Trump transition team. That is, Flynn most likely knew what was going down. Could be, too, why Flynn agreed to talk to the FBI without lawyers present. It was a counter sting from the get go.
If there were different versions of the call transcript, that would also explain why Pence said Flynn lied about what was on the transcript. He saw McCabe's copy.
As for the FISA's for other people, that could be explained by the DS panicking and realizing they needed FISA's ASAP to cover up the fact they had been surveilling without warrants. I think I heard that possibility floating around a few years back.