Should I stay the weekend? Friend's Dad

I planned this weekend to go and visit another city and stay for the night. Hotels are quite expensive and my friend told me she'd ask her Dad if I could stay the night.

Before I could even reply to the message, she sent me a screenshot of the programme her Dad had planned for the 2 of us this weekend and told me "He'd be really happy if you went."

I've only met her Dad twice and he seems very kind, but also intimidating; I'm shy and really not at ease at the thought of spending a weekend alone with him, even if it's kind of him to offer.

However, I feel like I can't really say no now. I'd be very happy to meet up with him for a couple of hours in the city, but I don't want to spend an entire weekend and spend the night at his just me and him.

As I said it's kind of him, and I know this is judgmental of me, but he was 54 and his wife was 26 when they got together and that's my age. I know it's just a number but I guess I find it a bit strange (and his wife will be away this weekend)

Any thoughts? Feel like I can't really say no... thanks