Create a table using DAX

Hi, 

I need to create a calculated table based on which customer name is manually added to a CustomerKeyFilter.

I'm trying to add three columns from table1 [CustomerKey], [QuestionId], [Answer] and three from table2 [GroupName], [WorkSpace], [QuestionLabel].

NewTable = 
VAR CustomerKeyFilter = "CustomerName"
RETURN
ADDCOLUMNS (
FILTER ( 'Table1', 'Table1'[CustomerKey] = CustomerKeyFilter ),
"QuestionId", 'Table1'[QuestionId],
"Answer", 'Table1'[Answer],
"WorkSpace",
CALCULATE (
MAXX (
FILTER ( 'Table2', RELATED('Table2'[id]) = RELATED('Table1'[QuestionId]) ),
'Table2'[WorkSpace]
)
),
"GroupName",
CALCULATE (
MAXX (
FILTER ( 'Table2', RELATED('Table2'[id]) = RELATED('Table1'[QuestionId]) ),
'Table2'[GroupName]
)
),
"QuestionLabel",
CALCULATE (
MAXX (
FILTER ( 'Table2', RELATED('Table2'[id]) = RELATED('Table1'[QuestionId]) ),
'Table2'[QuestionLabel]
)
)
)

It produces the following error:

The column 'Table2[id]' either doesn't exist or doesn't have a relationship to any table available in the current context.

The red squiggly line under 'Table1'[QuestionId] states:

Parameter is not the correct type.

Both columns, 'Table1'[QuestionId] and 'Table2'[id], are the correct names, they both exist and both data types are text.

The relationship between the two tables, via these two columns, is Many to one with a single cross-filter direction.

I've been looking for what seems like an eternity to find a solution which I can't seem to find.
I can't see what I'm doing wrong and as such, not sure how to fix it. Can someone help please.