How about if we create a new category here called “Old Forum” and move all the old data under that.
Even if it isn’t perfect and some of the formatting is messed up it will still be better than having to go to a totally different site with security warnings. Plus, it will then get indexed by Discourse and will be searchable right from here.
We would just have to be careful that it didn’t pull in all the users & groups and it didn’t start creating sub-categories under / and things like that. But, it should be doable. It just needs someone that can take the time to figure it out.