Joins across graph and database table

[lovgrandma]

Does anyone know the current limitations for doing joins across a graph and a database table?

I am fetching comments and I have the user like status (1 user - like - this comment) immediately available in the graph db and Im trying to do a join with the comment to the graph db.

WITH likes AS (
    SELECT 
        c ->> id AS post_id
    FROM cypher('customerA_graph', $$
        MATCH (a:userp { id: '70b5a93e-f9bc-4bd3-ad9f-a61d5aaf7a16'})-[b:like]-(c:post { id: '298dfb62-f000-43ad-b22b-abe4e5656395' })
        RETURN c.properties.id
    $$) AS (c text)
)
SELECT 
    g.*, 
    l.post_id AS likes
FROM customerA.posts g
LEFT JOIN likes l ON g.id = l.post_id
WHERE g.id = '298dfb62-f000-43ad-b22b-abe4e5656395';

Is it just because the vertex is JSON data or is there some other quirk of working with joins across relational to graph?

Currently getting

ERROR:  column "id" does not exist
LINE 3:         c ->> id AS post_id
                      ^ 

SQL state: 42703
Character: 43

Another attempt, query doesnt fail but column is empty

WITH likes AS (
    SELECT * FROM cypher('customerA_graph', $$
        MATCH (a:userp { id: '70b5a93e-f9bc-4bd3-ad9f-a61d5aaf7a16'})-[b:like]-(c:post { id: '298dfb62-f000-43ad-b22b-abe4e5656395' })
        RETURN c.properties.id
    $$) AS (c text)
)
SELECT 
    g.*, 
    l AS likes
FROM customerA.posts g
LEFT JOIN likes l ON g.id::text = l::text
WHERE g.id = '298dfb62-f000-43ad-b22b-abe4e5656395';