PostgreSQL Trigger to override insert on table with inheritance
You could possibly use lastval() or currval() to get the last value from the sequence. or use nextval() to get the id before the insert and then insert that value explicitly (instead of allowing the default value).

The third option is to ignore that column and instead use a natural key.  That you are able to get the ID by doing a select suggests that there is a natural key for this table.

Lastval and currval are private to your connection, so must be issued on the same connection that issued the insert.