BTW, I'm not medically trained, and base what I say on my own experience and other people's feedback.
I sent Mike's store an email. They replied automatically:
We are going to close the shop and retire on March 15, 2020. We are no longer taking orders for new equipment. Please check with Fairfax Ice or Medstar Capital Iceplex for skate fittings.
So I was probably wrong when I remembered that those freestyle skaters at Cabin John said they went to Ashburn. They probably said Fairfax, and the person you saw is probably the best in the area. My bad!
It is hard to believe such a person made such a fundamental error as measuring the foot too thin! There are a few other errors I can think of:
1. I already mentioned that raising the arch, by putting tape under the insole there, might (or might not!) help. Of course if you take that too far, that would hurt too.
2. Sometimes boot makers make mistakes, and make the boot(s) wrong. While I watched Mike work, there were a few cases like that.
3. While I watched Mike work, there was a case where a custom boot maker decided the change of measurement from a prior pair of boots to the current one was too great, and without asking, went back to the prior measurements. I found that almost impossible to believe, but you could call Jackson and ask whether that happened.
4. You mention the pain is at the ball of the foot, by which I assume you mean the position along your foot where the foot can easily bend upwards somewhat without breaking or over-stretching anything. Most boots bend upwards near where they
guess the ball of your foot is - possibly in order to make your feet less likely to slip forwards. If they guess wrong, or bend it too much, that can injure your feet. If I thought I might be slightly injured that way, I might GENTLY try bending my bare feet where the boots tries to bend them, and look for pain - but it's your choice whether to risk that. (You are risking it every time you put your feet in the boots.) If it does hurt like that in bent bare feet, see a good podiatrist. Perhaps you should see one anyway - but when I checked, a podiatrist wanted about $400 for an initial appointment!
5. This is probably completely off base, but it was true for me: if the bottoms of your boots and the insoles on them don't match the left/right tilt of your feet, so that there is unequal pressure on the two sides of each foot when you relax, you may be compensating by using muscles to make them touch equally, so you can control the edging of your blades. Eventually, muscle overuse makes those muscles sore. It takes at least a few minutes for the soreness to occur. Once again, tape placed in appropriate places under the insoles can equalize pressure everywhere.
I hate skating with the sole out as it hurts to stand on the metal plate on the heel...
I did get the cheap Target insoles and have put them in, I just need to test them out now.
You might need
a lot of experiments to get things right. So you could try first cutting a thin piece of cheap cardboard to shape. If that sort of works, then make adjustments: If the heel is loose, you cut it wider than the original insole there, so it wraps around your heel. Then you might want to try sticking layers of athletic tape (cloth first aid tape or coach tape is pretty durable, and doesn't change shape too quickly) in places on your home-made insole, like under the arch, to make things more comfortable. That might or might not make things better. Of course, it is possible to go too far, to the point where an extra high arch hurts too. Trial and error.
I personally try to create equal pressure on all parts of the foot, except that I try to keep pressure off the front and sides of the toes, and above the ankle, I leave enough space ahead and behind the leg so I can point and flex my ankles. As with everything, not everyone agrees exactly what to do.
But I still have no idea what to do about Nick's idea that you might actually be too tight, and cutting off circulation, somewhere other than the point where it actually hurts. If you can't trust what you feel, so you can't look for high pressure points. Some people have very poor circulation in their feet, and loose circulation easily, and/or cannot feel high pressure points on their feet. I hope that doesn't apply to you! I have diabetes, which sometimes causes that, and am worried that condition will occur. I have no idea whether compression socks would help.
I do hope you find a solution.