I am trying to set the version of SDE by using following code :

SET SERVEROUTPUT ON;
declare q varchar2(100);
ver varchar(10);
BEGIN
    DBMS_OUTPUT.PUT_LINE('HI');
    ver := 'PQ_358';
    DBMS_OUTPUT.PUT_LINE(ver);
    q := 'EXEC sde.version_util.set_current_version('''||ver||''')';
    DBMS_OUTPUT.PUT_LINE(q);
    EXECUTE IMMEDIATE q;   
END;

It gives me output as :

HI
PQ_358
EXEC sde.version_util.set_current_version('PQ_358')


Error starting at line : 2 in command -
declare q varchar2(100);
ver varchar(10);
BEGIN
    DBMS_OUTPUT.PUT_LINE('HI');
    ver := 'PQ_358';
    DBMS_OUTPUT.PUT_LINE(ver);
    q := 'EXEC sde.version_util.set_current_version('''||ver||''')';
    DBMS_OUTPUT.PUT_LINE(q);
    EXECUTE IMMEDIATE q;   
END;
Error report -
ORA-00900: invalid SQL statement
ORA-06512: at line 9
00900. 00000 -  "invalid SQL statement"
*Cause:    
*Action:

Any solution on this. Database: Oracle.

My objective is to run this code using C#.

Note: Cannot use StoredProcedure or function. Need to stick with c# code.