T-SQL - Casting from nvarchar to int & matching to nchar

Question

Using SQL Server 2008 R2 (SP1) on two separate database servers that are set up identically. Using already created tables and data, simplified for this example. The issue I am having is that one query returns data on both servers, and another query returns data on only one of them. I'm trying to identify and change the SQL setting or property that controls it.

tv_tbllOne (nchar) is joined to tv_tblTwo (nvarchar) and columns from each go in to tv_tblThreeA & tv_tblThreeB.

The table definitions:

    declare @tv_tblOne TABLE
    (
        [Record] [int],
        [Info1] [nchar](25),
        [DataFld] [varchar](20)
    );

    declare @tv_tblTwo TABLE
    (
        [idFld] [nvarchar](12),
        [DataFld2] [varchar](20)
    );

    declare @tv_tblThreeA TABLE
    (
        [idFld] [nvarchar](12),
        [tblThreeData] [varchar](20)
    );

    declare @tv_tblThreeB TABLE
    (
        [idFld] [nvarchar](12),
        [tblThreeData] [varchar](20)
    );

Here is the initialization for tv_tblOne & tv_tblTwo. tv_tblOne data [Info1 nchar(25) field] will always have a leading zero suppressed.

tv_tblTwo data [idFld nvarchar(12) field) may or may not have the leading zero suppressed. It could also be a 5 digit number.

INSERT INTO @tv_tblOne ([Record], [Info1], [DataFld]) 
VALUES (1, 6133, 'DataRec1'), (2, 31509, 'DataRec2'),
       (3, 8150, 'DataRec3'), (4, 10531, 'DataRec4')

INSERT INTO @tv_tblTwo ([idFld], [DataFld2]) 
VALUES ('06133', 'Tbl2DataRec1'), ('31509', 'Tbl2DataRec3')

INSERT INTO @tv_tblTwo ([idFld], [DataFld2]) 
VALUES (8150, 'Tbl2DataRec2'), (10531, 'Tbl2DataRec4')

This code produces results on both database servers.

    --Produced results on both DB Server1 & Server2
    insert into @tv_tblThreeB
    select 
        CAST(t1.Info1 as INT),
        t2.DataFld2
        from @tv_tblOne t1
        inner join @tv_tblTwo t2 on
        (CAST(t2.idFld as INT) = CAST(t1.Info1 as INT))

This code produces results on one server only.

    -- Produced results only on DB Server1
    insert into @tv_tblThreeA
    select 
        t1.Info1,
        t2.DataFld2
    from @tv_tblOne t1
    inner join @tv_tblTwo t2 on
        CAST(t2.idFld as INT) = t1.Info1;

The table variable tables represent tables on two separate databases on the same server. One and ThreeA & ThreeB would be located in the same database; Two would be in a different database on the same server. Neither query with the JOIN in them produce an error. On one server both return results; on the other server only the first JOIN query produces results.

Anything I've checked so far (properties of the column, table, database and server, collation) have been identical. Any ideas as to why the difference, or what to check/change?

Thanks!