Thanks,
Michael
1 answer
Hi Michael, this seems to be a set SFDC limitation. "no two fields can look up to the same type of record"
https://releasenotes.docs.salesforce.com/en-us/winter15/release-notes/rn_sales_activities_activity_custom_lookups.htm
I'm wondering if you can create a new custom object called approval that sits between the task and the user record.
Then you could create a lookup from the task to the approval object and a lookup from the approval to the user.
I noticed that adding an actual approval process to tasks seems to not be an option either since this idea is still out there: https://success.salesforce.com/ideaView?id=08730000000BrQCAA0