does the trimmer plus hedge attachemnt fit in a Ryobi?

yes, my ryobi and toro attachments are interchangeable.

Yes, but don't waste your money, it's junk. They break in the same place

It will fit a Ryobi unit as an accessory. The one I had was not machined correctly and broke after literally 2 minutes of cutting. The steel ring gear inside was too far away from the worm gear and slipped (no more movement of the cuting head)... Hopefully they fixed the issue, it appeared to be a very HD unit, well made short of the above issue...