That looks to be the case but I am fairly certain you don't add a bone to a mesh, you add the mesh to the bone, specifically the root bone that all other bones are parented to(does not need to be directly parented but parented to another that is parented to root or any number of bones in-between), then you parent the mesh to the root bone ie so the root is the parent - at least this is the case with Blender when I last tried. This is all done before vertex groups/weight painting takes place - by vertex groups I am referring which vertices are assigned to which bones as they can be assigned to more than one - this is separate from mesh/bone parenting which must be done first. This is what I had to do to get it into DBP as a .x file.
So with AppGameKit, in terms of memblock meshes I imagine you would prepare a memblock with all the right attributes and data then swap out an existing objects mesh that has children(setobjectmeshfrommemblock rather than addmeshtomemblock). So if all that is considered true(as I have not tested but just looked at all available commands and applied it to the knowledge I know of), then it would perhaps be best to take the .dbo and convert it to an AppGameKit loadable file format and just load that rather than trying to import direct into AGK. That is my thinking anyway, not necessarily correct so please bare that in mind, I am essentially basing it on the fact that you would need to duplicate the minimum framework as a loadable AppGameKit format to work on in which case you might as well just do the whole thing as a file format conversion.
Win 10 Home 64, Intel(R) Core(TM) i5-10300H, 8GB DDR4, NVidia GeForce GTX 1650 4GB GDDR6