I hope you got some movement on it by now.
In case not (and possibly for future purposes) I believe you are talking about the bushing in the steering knuckle that steadies the lower control arm ball joint.
It is conical btw.
Here are some pointers for the job:
1. To help a spinning bushing like that, I just find a way to put pressure on the joint, for example by putting a jack under the knuckle, then try turning it.
2. If you buy a used control arm, it will possibly come with that cone still attached.
3. Used control arms can be a gamble - test the ball joints properly, along with the bushings.
4. If you buy a new control arm, it will most certainly NOT
come with the cone attached. Video discussing new control arms
5. You can remove your old cone and reuse it, it's just metal after all. Cone removal video
6. If you choose to buy brand new, the ball joint bushing for the front is part # 40173-EG000, and for the rear it's part # 40173-33P00.
7. Other control arm videos that might be helpful to some - Click link to see youtube playlist