The short answer is yes.
Most professional e-learning providers will supply you with the source files for your project. These files cannot be loaded to your LMS but they are the files that you need to make updates and changes. They will be in the format of the program that created them, so for storyline files, they will be a .story file, for Captivate a .cptx file and so on. It doesn’t matter if you can’t open them – any professional e-learning developer will have the software that is required to work with them.
A professional elearning developer will also be able to work with your formats and stick to the same layout as your existing courses (if that’s what you want). So, as long as you have the source files, you can shop around and find an elearning developer that better suits your needs.
Feel free to get in touch if you need any more information.