AND function on PowerBI slicers

still not sure but try :

Selected Measure Value = 
    SWITCH(SELECTEDVALUE('Measures for Slicer'[Measure])
        , "Managers", [Manager Names]
        , BLANK()
        )

Selected Measure Value (only for managers) = 
    // Get the number of managers you selected
    VAR SelectedmanagerCount = CALCULATE(COUNTROWS(VALUES(table[managers]))
                                        , ALLSELECTED(table))
    VAR output = SUMX (
        VALUES( table[manager] ),    //Get each manager in the current context
        VAR x = ADDCOLUMNS (            //For each manager, set a flag for whether 
                                        //there is data for each selected manager
                    ALLSELECTED ( table ),
                    "Flag", IF ( NOT (ISBLANK ( [Selected Measure Value] ), 1, 0 )
                    )
        //Count up the number of sales with data for each manager
        VAR salesWithDataFormanager = SUMX ( x, [Flag] )
 
        //If the number of managers for the facility matches the number of 
        //selected managers, include that value, otherwise exclude it.
        RETURN
            IF ( salesWithDataFormanager = SelectedmanagerCount, [Selected Measure Value] )
        )
    RETURN output