I received a message saying I needed a day pass to drive through Yosemite , with a link for facility 300015...but I still can't get a ticket. Am I missing a way to ensure that I can drive? otherwise, I must cancel, too much of a risk otherwise

Several ways to get your permits to enter the park: 1.) Day-use pass $2+(yearly pass or $35). 2.) In-Park Camping, Lodging, or Vacation Rentals - not sure related this or not, with your 300015. Check out by yourself. 3.) Wilderness or Half Dome Permits. 4.) Group permits. https://www.nps.gov/yose/planyourvisit/reservations.htm

You can still go in the park if you booked a tour. We booked a day tour through Incredible Adventures and had a great experience. Call them 8007778464.

You must have A-day pass

You have to have the Yosemite Day Pass or you can't go in the park at all

Not sure what facility 300015 is, but maybe try getting the day pass from https://www.nps.gov/yose/planyourvisit/fees.htm Hope this helps, as the alternative is to drive around the park.