Hi Ray,
Thanks for the post and our sincere apologies for the delay in response. For this requirement, you will basically have to create two resource groups and trigger a password reset. Navigate to Resources-->Resource Groups and create new group with the following criteria.
Resource Type Equals Windows+
User account Equals Administrator
Save this Group and this will contain all the local admin accounts together. Use the "Perform Password Reset" button present next to this Group and supply the password of your choice. Then use the same steps to create another group but with the other user account. So you will have two groups and for both groups, you can use two different passwords.
Please try the same and do contact us if you have any other questions.