I have tested it. Queries with regex are case sensitive even through the nodejs driver. That makes sense as the driver is only forwarding your request to the DB. It behave in exactly the same manner as it would from the visualiser.
In my data I know to have an email that has the value: firstname.lastname@example.org
if I query for:
match $e isa email, has value $val; $val val /.*member.*/;get;
It is returned, but if I query for
/.*Member.*/ it is not. this is the expected behaviour.