How was Chuckie involved in the assasination of Hoffa?

Question

In the movie The Irishman Chucky came with his car, and then Frank and Sally Bugs approached the car. Sally Bugs and Chuckie started a little drama so that they could strangle Frank (this is what I have inferred) by making him to sit in front. However, they failed in making him sit in front.

Then they drove to Hoffa’s and after a little conversation between Frank and Hoffa, they drove him Frank and Hoffa to the place where Sally Bugs and Frank got the Chuckie’s car. After this, Frank and Hoffa went inside the house and Hoffa was assassinated. We can see in the movie that Sally Bugs and Chuckie drove away (to me it seems that they knew why Frank took Hoffa there).

So, can you please explain how Chuckie was involved in his father’s assassination? And Why he was involved when he saved his father from a an assassin during the trial?

Any references will be appreciated, like from I heard you paint houses or Vendetta: Bobby Kennedy vs Jimmy Hoffa .

Answer 1

I'm only basing this on the script, but it appears it was a combination of being Jimmy's foster son (not blood), being in the mob life, and Chuckie not being too smart to begin with.

See the script here starting around page 110.

Chuckie was Jimmy’s foster son. He was in the thing too but didn’t know it.
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All Chuckie knew, he was picking up one of Pro’s guys - Sally, who he didn’t know - and me - who he did know - and we were all picking up his dad at the Red Fox for a meeting. He was in it, as you say, stupidly.
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I felt sorry for Chuckie. If anyone deserves to be forgiven, it’s him.