It's not possible. For DynamicLink to work correctly, all files must be at the same version level in both programs. the file must be opened in AE CC 2017 and saved. And honestly: Work on that awful file and folder naming and don't store your work files on the desktop. Basics!
Felling very bad to listen that the files of same product with different version not working with latest version. This is absolutely I will say the low knowledge of developers of cc 2015 and 2017. They should consider this in new version that their software should accept old version files as normally other sofwares of different companies supports.
It does support older AE files, just not through dynamic link.