To be really worried about missing cat?

[NotSafe]

Our cat is 20years old.
She is always here, sprawled out on whichever sofa is in the sun. She rarely goes outside (except to sometimes nap on the patio furniture) but DH and I just realised that we haven't seen her since 2pm ish?
We have been out and looked for her but have acres of very dense woodland at the back of the garden which we would need to chop through with shears to get into.
I'm so worried as we have foxes, badgers and buzzards regularly visiting the garden.
What should we do now?

She is very vocal usually, so if we call her name she always loudly replies. If she was in the house or woodland I think she would answer.

Can you leave a window open tonight?

Can you both go out together looking

I hope your kitty comes home safe and well soon.

I hope you find her. Always worrying when they are gone longer than usual

My cat was 19 when she developed severe dementia, on top of other medical issues. Towards the end she would go out of the house and forget where she lived. I put a request on the local Facebook page a couple of times and she had just been at other houses which had cats.

Have you tried that?

Some cats leave their house at the end of their lives. They curl up somewhere to die in peace.
Not to shock you, but it is something to be aware of, it is a natural thing for them to do.
💕