If the comment refers to the events in SK, it was Winter who provided the access to the Ways. In SK, Summer specifically refused to offer help, saying, "Queen Titania does not now, nor will she ever choose sides in the disputes of mortal and anthorphage. She bids both Council and court alike to keep their war well away from the realms of Summer. We will remain neutral." (Ch 5, p 63 paperback) Mab offered to let the Council travel through her realm if one request (which all soon learned meant Harry's service as her Emissary) was fulfilled (p 75).
As of the end of Harry's meeting with Mab, Harry had stated he would think about her request, and retained the option to refuse. He didn't actually commit to taking on the task until the Gatekeeper made it his condition for voting in Harry's favor at the Council meeting.
Maybe the RPG text is referring to other help Summer provided, such as the battle against the Rampires mentioned in Proven Guilty? I'd think that was more than mild assistance, but understatement is an art.