To meet your requirement of accessing private SharePoint content in Dynamics 365 Knowledge Base with updates and keyword search, here are a few alternative approaches:
1. Scheduled Data Sync with Power Automate or Azure Logic Apps:
Use Power Automate or Azure Logic Apps to set up a scheduled flow that connects to SharePoint with the necessary authentication and pulls article updates. You could use the SharePoint REST API or Microsoft Graph API with the necessary permissions.
Store this data in a custom entity in Dynamics 365 to simulate the Knowledge Base article structure and ensure that keyword search is enabled.
2. Custom API Service:
Create a custom service that authenticates with SharePoint to pull the data and expose it through a REST API. This API could then be consumed by Dynamics 365, either directly or via a plugin or custom page, for on-demand retrieval.
You could then build a custom Knowledge Base interface within Dynamics 365 that queries this API, potentially providing more flexible search and retrieval options.
3. Azure Cognitive Search Integration:
Index the SharePoint content in Azure Cognitive Search with scheduled refreshes. Then, set up a connection between Dynamics 365 and Azure Cognitive Search using APIs.
You can implement custom UI components in Dynamics 365 that leverage Cognitive Search’s keyword and AI-driven search features.
4. Custom Knowledge Article Search Plugin:
Build a custom plugin that interfaces with SharePoint via Microsoft Graph API, triggered by events (e.g., on load or on demand) within the Dynamics 365 Knowledge Base interface.
Use Azure AD Application permissions to authenticate to SharePoint, even if it is outside the Dynamics tenant, as long as the SharePoint and Azure AD instances can connect.