OK, I don't know whether or not the squash will be green. What I
should have said is we don't know what color it will be. I did say it
would likely be green since this was a possibility previously
mentioned. Green is a color which is possible. Likely may have been
an innacurate adjective. I should have used possibly.

To JoeSpareBedroom: Actually I did not suggest successful cross
pollinations were impossible. I did not use the word impossible at
any point in my post. Quite the opposite in fact. I said that they
were notorious outcrossers. The word successful, in my mind, would
only refer to the production of viable fruit and seed. While the vine
will produce fruit and seed, it will not produce squash that is like
the parents unless it were grown either in isolation or by performing
hand pollinations. It is still successful from the standpoint of
producing fruit and seed.

We don't know anything about this seed including whether or not it is
even a pumpkin. What we do know is that it will product some kind of
fruit and seed, given a chance. What kind of squash it will produce
is unknown. Anything is possible. It is also possilbe that it will
grow squash that is true to type if the seed was originally grown in
isolation. We can never know in this case because the orignial type is
unknown. In the case of field pumkins it would be entirely possible to
get a pumkin since they are grown in large field and probabley not many
other squash nearby. This would qualify as isolation. We cannot know
one way or the other since the origin of the seed is entirely unknown.
All squash or pumpkins are edible, more or less. Whether or not they
will grow true to seed is the point I was making.