Should I suck it up and stay the whole time?

I just turned 21 and have a 7 month old who takes 3 naps a day every around 2 and a halfish hours. My mom wanted to throw me a party for my birthday at our house at first but then changed it to some park that costs like $40. While I am grateful for this party, she offered it and scheduled it for 1-5pm and didn’t ask me if it was an ok time, or even if the day was ok, and she’s inviting people I don’t really know. I told her my daughter has naps during that time and I dont know if I’ll be able to stay that long. My daughter refuses to sleep anywhere that is a different environment than our house, it’s too stimulating for her. I’ve tried baby wearing, pack and plays , etc.. she won’t sleep anywhere but our house. My mom got upset and said she spent this money..etc.. on me for this party, but like I didn’t ask for it? She completely offered and is using it against me. Like I said I’m grateful, but it’s hard to make it that whole time. She keeps saying “we can bring her something to sleep in.” And “I only made it that long so people can come and go when they’d like.” But really it’s an inconvenience to my daughters sleep schedule. I thought we would be having it at our house which would’ve been better, but instead she changed it up and told me it’s at this park. Before she scheduled it, my boyfriend told her it would be hard for us to be there that whole time because of our daughters naps but my mom didn’t listen I guess. Do I go and skip my daughters naps?