I'm not sure if you intended to reply to my message in your original post, or if you simply clicked "reply" on the last post at the time, but I'll address your question anyway. If you've read much of my stuff you can probably tell I'm not a big fan of surgery, for other reasons including potential nerve damage as may be your case (peroneal nerve?), but it may be too late to discuss that. With any luck, perhaps there is scar tissue resulting from the hip surgery that has put pressure on a nerve trunk leading to the area of dysfunction, but I doubt it. It is also risky opening people up to see. Perhaps there is an MRI that can illuminate the problem, but for now you must deal with it.
SInce the drop foot results when the dorsiflexors are dormant, it occurs to me that dorsiflexion may not be necessary when your plantarflexor muscles are much more powerful than their weaker antagonists, if you'll pardon the redundancy I use for emphasis. If I were you - and I offer this in all seriousness - I'd hook a long bungee cord from my waist band to the lower laces of my shoe to mimick the dorsiflexors and take 'er out for a spin. The plantarflexors already take on a much greater load than that bungee just propelling you forward, let alone running, but I digress.
Meanwhile, there is that neuroma factory down there. Please note that neuroma surgeries are not final. The tendency to create one (or two in your case) is a virtual guarantee to create more if the cause is not removed. Much surgery as medicine is remedial and practiced as a last resort. The only preventive surgery I could see would be 1st to restore function to your foot and 2nd to remodel the bone structure to make neuromas unlikely. This is rarely done and probably not covered by insurance, and yes there would be huge risks involved according to accounts I've read but failed to bookmark. My money's on the bungee - or some high tech equivalent.
You asked whether drop foot is known to lead to neuromas. A brief search found no discussion of this, but in my opinion it goes without saying, and the Dr's conclusion is logical. This is why I keep thinking Cause and not about endlessly chasing Symptom. I did however, find a short discussion of potential nerve damage during hip surgery.
Another possibility occurred to me as an afterthought, even though it concerns my area of expertise. Surgery often causes muscular spasm, and hip surgery would be likely to cause some dysfunction in the muscles of the hip, some of which might be dangerously close to branches of the Sciatic Nerve, which of course feeds the Peroneal Nerve that is apparently not activating your dorsiflexor muscles. Knots called trigger points are potentially powerful enough to do this in the right location(s), but muscles in spasm also tighten other structures through which nerves pass, including vertebrae like L5, an area that is associated with drop foot and tends to be one of the first to weaken with age.
A piece of information that could help is whether or not your drop foot is accompanied by Trendelenburg or stepping gait, both evidence of hip muscle dysfunction. Meanwhile, lets look at some of the interweaving that goes on between muscles and nerves... http://en.wikipedia.org/wiki/Superior_gluteal_nerve
Tracing upward from the Peroneal nerve that activates dorsiflexion, you can see its origins in the jungle of gluteal muscles illustrated in the link above. Note the powerful hip rotator muscle Piriformis which in some persons wraps around the Sciatic Nerve that carries nerve impulses to your lower leg. Problems with this and other nuscles in the gluteal area could conceivably affect portions of the Sciatic Nerve. It would be interesting to see if palpation and manipulation of this area could restore some function, but this may already have been tried after your unexpected condition was discovered. Prognosis in these cases is normally not good but if not tried it's worth a shot, especially if the onset was not immediate but gradual.
Ok, I've given you enough to think about for now, so I'll go about my business, wishing you every possibility of full recovery.