I got it to load! How I did this was opting out of the FS2024 beta so I could download the from the FS marketplace instead of just streaming it and then it loaded in within seconds. To me it seems the beta was a problem but I that may just be for me.
I am having the same issue and did the same steps you did. Never got to fly the plane I bought which is disappointing. Hopefully this gets fixed as the a340 looks really good!