DIctionary views missing from internal SQL when connecting via VPN

When opening Schema browser while connected to a database via VPN, I'm bombarded with ORA-00942 error messages.

Using SQLTracker, I've identified the offending SQL as 

-- Session: SCHEMA_NAME@INSTANCE

-- Timestamp: 09:56:26.600

Select t.trigger_name, t.trigger_type, t.triggering_event,

        t.when_clause, t.status enabled, null status, t.owner, -1 object_id, t.trigger_body

from sys. t

where t.table_owner = :own

and   t.table_name = :obj;

:own(VARCHAR[16],IN/OUT)='SCHEMA_NAME'

:obj(VARCHAR[25],IN/OUT)='SOME_TABLE_NAME'

When connected to the database without the VPN, the same SQL reads as follows :

-- Session: SCHEMA_NAME@INSTANCE

-- Timestamp: 10:01:17.618

Select t.trigger_name, t.trigger_type, t.triggering_event,

        t.when_clause, t.status enabled, o.status, t.owner, o.object_id, t.trigger_body

from sys.DBA_OBJECTS o, sys.DBA_TRIGGERS t

where t.table_owner = :own

and   t.table_name = :obj

and   o.object_type = 'TRIGGER'

and   o.object_name = t.trigger_name

and   o.owner = t.owner;

:own(VARCHAR[16],IN/OUT)='SCHEMA_NAME'

:obj(VARCHAR[25],IN/OUT)='SOME_TABLE_NAME'

This is connecting to the same schema, same database instance. Attempting to browse objects owned by the connected schema.

Any ideas / suggestions on why this behaviour happens ?

Using Toad for Oracle 12.12.0.39 - Although same behaviour experienced in previous versions as well

Thanks in advance

~N