Hello there, and welcome to the forums!
Thank you for posting all the steps you've done, it helped me search for something that you can still try.
Please take a look at this post by @Bob_Headrick. I know you mentioned cleaning the printhead, but I'm not sure if you've had a chance to soak it yet. Please read over his post, and see if those steps help at all.
Feel free to post back with any further questions, or any other symptoms the printer is having.