In addition to the default Mendix integration documentation and the OAuth module, this post is particularly useful for setting up SharePoint authentication/authorization.
Mendix provides a range of possibilities for integration (soap, rest, odata, file). You could take a look at this page more information.
Seems that you got clarity on Mendix possibilities for integration (soap, rest, odata, file). Still if you need help about SharePoint integration Services part ping be once. Will help you the best.