I doubt the rootstock is laceleaf ( that doesn't follow much logic)...Rootstock is most likely plain old Acer Palmatum...I'd say chop to the rootstock...Graft's are bad, and as soon as you learn this, the better....Ill post a pic of JM similar to that(much smaller) that got the chop to the rootstock, and I actually got it to bud...In one stupid place, but yeah...Ill post....And if you want any of that green maple, just airlayer before you chop....