I'm afraid I have more questions than answers at this point:
-  if this temporary database you're rebuilding things in is in the same instance, then wouldn't that also be...

You would have to run that in each database, I couldn't figure out an easy way to do one script that automatically runs for all databases.  I probably should have...

How will the data be presented?  It may be best to use something like a Pivot table in Excel or whatever reporting tool to do the pivoting for you.  It...

building on Jeff's idea, you can also check the dynamic management views to see what queries are taking the most CPU, I/O, or total duration if you run this in...

for SQL authenticated users it's fairly easy, for Windows authenticated it's a bit more complex because you have to consider groups:
CREATE TABLE #OrphanUsers (UserName nvarchar(128), UserType char(1));

--SQL...

Where I'm working at, the developers know if they want to make development easy they just have to say "database" or "SQL" or "Harshman" enough times, and I'll show up...

here is a most basic Calendar table that could help.  With any of these techniques performance could vary depending on your system and data:
/* create and initialize...

How is your Excel Source configured?  I've solved similar problems by setting the Data access mode to "SQL command" then writing a query such as:
SELECT * FROM...

Did you run that statement in the database that you are checking permissions in?  Sorry, I guess I could have explained that better.

I thought mirroring was deprecated in SQL Server 2012... even though it still seems to be functioning in 2016.

The first thing I notice is that there seems to be a big problem with statistics here... there are nodes that say estimated rows in single digits but actual rows...