Invalid Object Name when attempting to insert data from a table in one DB to a table in another DB on the same server

I am attempting to perform an insert from a table in one database to a table in another database on the same server I have tried this:

INSERT INTO SDCS_AUDIT.BMA_FORM_DATA (.....)

and this:

INSERT INTO [SDCS_AUDIT].[BMA_FORM_DATA] (...)

as well as this:

INSERT INTO DATABASE_Name.SDCS_AUDIT.BMA_FORM_DATA (...)

and this:

INSERT INTO [DATABASE_Name].[SDCS_AUDIT].[BMA_FORM_DATA] (...)

I have also attempted to add the server name in front of the database name but it doesn't like that either.

I know that you need to use sp_linkedserver to create a linked server if the dbs are on two separate servers but from my understanding I shouldn't have to do that if they are on the same server.

Intellisense doesn't show any of the other databases on this server. Is there an option I have to turn on/off somewhere or am I making a bonehead mistake somewhere? This is inside of a trigger by the way, in case that matters.