As Jesus was speaking in the present about a future action, and God forgives sins, Jesus wasn't refusing to do it, He couldn't do it, because no desire for forgiveness yet existed. Jesus could not accept what wasn't being offered and asked God His Father to accept it, should it be offered in the future. If Jesus could have accepted and forgiven them He would have, as He did with the thief on the Cross.
“As Jesus was speaking in the present about a future action, and God forgives sins, Jesus wasn’t refusing to do it, He couldn’t do it, because no desire for forgiveness yet existed.”
You keep hinging your arguments on the assertion that forgiveness requires a prior request. So, a single example of forgiveness without a request from the Bible should serve to show you the flaw in those arguments. I offer the example of the woman who bathed Christ’s feet in Luke chapter 7. He tells her, in verse 48 “... Thy sins are forgiven.” Yet, she never asked Jesus for forgiveness.
According to your argument, it would have been impossible for Jesus to forgive her, yet we know that He did, so the flaw can only lie with your argument.