Unlimited has never really been truly unlimited.  The current definition can be found in the MAXSIZE section of this page:
https://docs.microsoft.com/en-us/sql/t-sql/statements/alter-database-transact-sql-file-and-filegroup-options?view=sql-server-2017
Do you really need a TEMPDB transaction...

If statistics are out of date, that does NOT mean that they aren't being used, that typically means that the table they are on is large enough that SQL Server's...

the oddest things on my desk are:
-  a robot pencil sharpener that doesn't really work because sharpening a pencil winds it up so you can only turn the pencil...

OK, I can't make any sense of the pictures you've attached.  Are you trying to create a foreign key from model to modeloption?  If so, and if modeloptionID is the primary...

I think it depends if your Execute SQL task is using an OLEDB connection or ADO.NET connection to the database, they work differently.
If using ADO.NET connection then you use...

The question assumes I'm not already burnt out, which I'm fairly certain that I am.  I try to manage it so that the side effects of being burnt out don't...

One more place to check is in the base_object_name of sys.synonyms.  That might hide the fact that a query is really using a different database.