I had a somewhat similar clog once, and I could fix it back up. However, it is a lot of work.
Step 1: heat
As long as the heater cartridge is still ok, just fire up the printer, move up the printhead by 50 mm and wait some two or three minutes till the goop is warmed enough at the core to melt. Set the hotend to 200 °C and no cooling fan.
Step 2: rough clean
Just pull at the outer of the blob to pull it down. Then grab some tool like pliers and pull off the worst that still sticks to the hotend. Pulling the blob free can take a while, so be patient and careful.
If you have a soldering iron, you can use that as a heated scraper from the outside and skip on heating from the inside.
Step 3: Cool down
After having made a rough clean up from the outside, let it cool down so you can dismantle it.
Step 4: dismantle and clean the hotend.
This is actually rather simple, and I will point to a question where I outlined that for a broken thermistor cartridge. You have a working thermosensor at least, so less problems on that front.
If you have a hot air gun for hot air soldering, you can be much faster! Skip step 1 to 3, dismantle the hotend and go straight to Step 4, dismantling it and cleaning it out of the machine with the hot air soldering tool as a heat source. Heat and scrape away, and get out the thermosensor and thermosensor as soon as possible to prevent destroying them.