I had exactly the same problem as you, OP. I couldn't feel anything inside a vagina at all. I got some ED drugs and tried again and felt nothing for around ten minutes. Literally, using my fingers would have been more fun. Unfortunately, I haven't been able to quit MO, so I can't tell you whether you would recover totally or not.
However, I did quit PMO while continuing to MO for two stretches of around 50 days. Before this, I couldn't finish to softcore porn or to MO without visual stimulation, though I could get an erection to both. After the stretches, I could finish to both, though without visual stimulation, it always took about 20 minutes. So, basically half a reboot changed me from anorgasmia to DE and I suspect a proper reboot would finish the job. I did also do some CBT for typical sexual anxieties, though.
Now, a fleshlight isn't great IMO. Firstly, put two fingers into the front when it's in its case and notice how tight it is. Mine is genuinely tighter than my deathgrip. The rear end is slightly looser, but I think deathgrip is the more minor issue and porn is the more major issue. Besides, fleshlights aren't textured like vaginas internally, they're designed to be super stimulating.
Deathgrip/idiosyncratic masturbatory style is likely contributing, but if you're addicted to porn, I think there's no way they're the only problem. I think you really need to quit PMO and MO for three months and try to finish on your own without visual stimulation. Once you can do that, get a partner and go to sexual therapy if you still have DE and you'll get sorted. If you can't get a partner, do surrogate therapy.
Anorgasmia can be scary because it's reputed to be hard to treat according to books I've read, but most of them were a few years old and it's unclear (and unlikely) the authors tried full abstinence for 90 days like rebooters do, so I think your odds are better than you may think.
Good luck man and keep your chin up,