Filter values from one table in another without relationship DAX

Hi talespin  Please see the solution below. As you mentioned earlier creating a measure using the formula wasn't the right way and creating a role and applying RLS was the right approach. Since no one was able to provide a RLS DAX query for this requirement we have itself come up with a DAX solution to achieve the requirement. Please see below. 

1.) All semi-colon values in DIM_ACT columns must be replaced by "|" symbol for this formula to work. Either change the source data or create a calculated column to replace ";" with "|".

2.) Eliminated DIM_USER table and brought in EMAIL ID column to DIM_ACT table itself. 
3.) There is only 1 record for a single user in DIM_ACT under a single GROUP.
4.) Create a ROLE in Manage roles and apply below DAX under FACT_ACTUALS table. Using the below DAX , when the user logs in he will be able to see only the values separated using "|" in the respective columns of DIM_ACT and when ALL is present in any of the columns, he will be able to see all the values available in FACT ACTUALS.   

/* FILTER DIM_ACT TO FETCH THE RECORD HAVING ONLY THE LOGGED IN USER EMAIL ID & VALUES ASSIGNED UNDER LEVEL COLUMN */

&& [LEVEL]
IN

(
VAR _LEV =
MAXX (
FILTER
( 'DIM_ACT',
[EMAIL ID] = USERPRINCIPALNAME () ),
'DIM_ACT'[_LEV]
)

/* TAKE THE PATH LENGTH OF LEVEL COLUMN. THIS IS DONE BECAUSE THERE COULD BE N NUMBER OF VALUES SEPARATED BY | SYMBOL IN DIM_ACT TABLE
AND WE NEED TO SEPARATE THEM AS INDIVIDUAL VALUES */

VAR _LEVLEN = PATHLENGTH (_LEV )

/* CREATE A VIRTUAL TABLE WITH COLUMN NAME LEVLIST HAVING THE LIST OF LEVEL COLUMN VALUES */

VAR _LEVTABLE = ADDCOLUMNS ( GENERATESERIES ( 1, _LEVLEN ), "LEVLIST", PATHITEM ( _LEV, [Value] ) )

/* SELECT THE COLUMN VALUES AND PASS THE VALUES TO LIST */

VAR _LEV_list = SELECTCOLUMNS ( _LEVTABLE, "LEVEL", [LEVLIST] )

/* ADD ALL THE LEVEL VALUES FROM FACT_ACTUALS. THIS IS FOR A USER WHO HAS VALUE "ALL" ASSIGNED TO HIM UNDER LEVEL IN DIM_ACT TABLE */

VAR _ALLFACTLEV = ADDCOLUMNS ( VALUES ( FACT_ACTUALS[LEVEL] ), "ALL", "ALL" )

/* RETURN ONLY THE VALUES ASSIGNED IN LEVEL COLUMN IN DIM_ACT FROM FACT TABLE FOR LOGGED IN USER OR RETURN ALL THE VALUES FROM FACT TABLE WHEN THE LEVEL COLUMN IS PROVIDED AS ALL */

RETURN
SELECTCOLUMNS
(
FILTER ( _ALLFACTLEV, [LEVEL] IN _LEV_LIST || [ALL] IN _LEV_LIST ),
[LEVEL]
)
)

&& [LABEL]
IN (
VAR _LAB =
MAXX (
FILTER ( 'DIM_ACT', [EMAIL ID] = USERPRINCIPALNAME () ),
'DIM_ACT'[LABEL]
)
VAR _LABLEN = PATHLENGTH ( _LAB )
VAR _LABTABLE =
ADDCOLUMNS ( GENERATESERIES ( 1, _LABLEN ), "LABLIST", PATHITEM ( _LAB, [Value] ) )
VAR _LAB_LIST =
SELECTCOLUMNS ( _LABTABLE, "LABEL", [LABLIST] )
VAR _ALLFACTLAB =
ADDCOLUMNS ( VALUES ( FACT_ACTUALS[LABEL] ), "ALL", "ALL" )
RETURN
SELECTCOLUMNS (
FILTER ( _ALLFACTLAB, [LABEL] IN _LAB_LIST || [ALL] IN _LAB_LIST ),
[LABEL]
)
)

&& [SOURCE] IN ------ Similarly repeat the above code for other columns in DIM_ACT