It is the root stock that will regrow, not the HC. That is a sucker from the root, right? looks like enough to graft onto in the spring. Your new tree will grow faster with an already established root system vs starting over. If you don't have other HC trees I can send you a couple scions for the cost of postage. I believe it is a protected cultivar, but in this case I don't see how anyone can object.

Also I can give some grafting pointers if you have never done it.

cckw thanks for all the help......I've got some other honey crisp trees thanks for the offer,I may take you up on some grafting advice or tips this spring, I've never done it before.I've got a few other apple varieties that I planted 3 years ago that I don't really care for and was thinking about trying the grafting with some HC scion in the spring.

Honeycrisp is off of patent, so have at it.

If it broke at the scion junction I might worry that it is a delayed incompatibility and might choose a different variety to graft to that rootstock, especially since you have other honeycrisps.

Do you know the name of the rootstock?

I Believe honeyvrisp is known for brittle graft unions with a number of rootstocks....it's a great apple but has a number of challenges in growing, harvesting and storing.

I have posted this idea before and I haven't seen any posts of objection. When I do Honeycrisp again I am going to start the tree as something like Liberty then add individual branch grafts of honeycrisp, but less then 50%, to have a healthier tree backing up the apples. I have done this the other direction to get some strong foliage on my HC tree since the HC leaves get attached so badly by bugs, rust, and whatever else.