Just be frank and flexible.

Say:

1. We don't have that stuff. As a startup with customers that love customized solutions, we've tried to be nimble.

2. But I can see that your organization needs a streamlined process. We can deliver.

3. This stuff isn't for us internally. But show us some examples of what you'd like to receive, let us know how it's used, and we'll produce whatever is needed.

In other words, treat your big marketing partner as a client. Bring a white board, listen, and produce!