It appears that your reason for agreeing to the visit is mostly because you want to find out WHY, after all this time, they want to visit you.
Does it really matter?
Don't concern yourself with WHY they want to visit. Concern yourself with whether or not you want to be in a room with them while they present their one-sided arguments to you.
They are not coming for a social visit. They are not coming to apologize to you and they are not open to hearing your "side" of the story - a story that ended 8 years ago when THEY slammed the book shut. They are not there to rewrite history. They are on a mission, most likely because the CO went thru the files and demanded from the elders an update on your status. They want to either invite you to come back (on their terms) or they want to figuratively spit in your face once again and reiterate their view that you are unworthy of life in God's New Order. Not because they care about your spirituality, but because they want to update their files. If they did care about you they would have contacted you much sooner.
If you had been disgracefully fired from a job 8 years ago and that former boss now wanted to visit you, would you agree to the visit?