If the loss of that branch would destroy the profile of the tree then I would try to save the limb. I have had good luck putting trees damaged by wind or ice/snow back together again.
Since Dogwood, Cornus floridia, is a hard wood that has excellant screw holding capability I would first pull the limb back into position with a light cable and then install several galvanised or stainless steel wood screws or threaded rod depending upon the actual diameter. When the screws or rod is installed be sure to install one screw at each end of the split to prevent the split from lengthening, then install more along the length of the split, depending upon how long the split is. Since the dogwood is so hard it is important to be sure to pre-drill each hole 1/16"(1.6mm) undersized before threading in the screws or rod. By threading in the supporting screws instead of using nuts and washers you damage less of the cambium layed of the branch.
Good luck. As others have said. If it does not work you can always cut it off later. But I think it is definitely worth trying to save it if it is an important branch.
If you are looking for a different arborist in your area you can always go to the ISA, International Society of Arborculture, web site and check for members of their organization.
International Society of Arboriculture