How to include an additional approvar in a Promotion workflow? When there is a compensation or position changes require one additional approval as well
The best way to trigger different workflows is by setting up business rule based on the events/data change. In your use case, whenever there is a promotion or change in compensation or position, call workflow by set command.
Set <hris>.Workflow Information to be equal to <workflow>.
The business rule must be under "onSave" event type.
You may wish to explore such questions on the launchpad first (https://launchpad.support.sap.com/ , soon to be me.sap.com) next time, as it may save you time and as the answer is more comprehensive than what we could share here.
As indicated by this KB: https://userapps.support.sap.com/sap/support/knowledge/en/2080722, there is a feature, but this is often not something approvers have access to. Either you investigate a way to incorporate this, or your customer looks for ways to request this approval outside of the system (and potentially adds text/attachments as proof of the approval in the WF request). In my knowledge there is no alternative to these 2 options.