SEVEN AT THE GOLDEN SHOVEL. (subtitle)
The "golden shovel" could make you think of death and grave digging. Why is the shovel "golden"?
Lurk late. (line 3)
If any of the lines can be tied directly to the final prophecy, "die soon," we think it's this one. A person who "lurks" generally doesn't want to be seen by other people. It's a form of hiding. Why don't the pool players want to be seen late at night? Or do they care?
We Sing sin. (lines 4-5)
OK, so maybe you could tie their celebration of sin to the last line as well. However, the poem doesn't mention any particularly terrible sins: drinking, carousing, and skipping school.