compost it just don't eat the compost before it's done.

I've used the shredded leaves/stems in my garden for years, with no ill effects on plant or animal life. [earthworms thrive in area under my philo] I think the poisonous if eaten warning is for livestock or small children. Pretty sure that the plant parts are not as toxic as oleander ... see link below for data on composting oleander leaves [safe]

You've probably discovered that the sap stains clothing. I've not noticed any skin irritation. Hope this helps.

Here is a link that might be useful: Composting oleander

That post says that the leaves are poisonous if eaten and the sap can irritate skin. So compost them but do not eat them or rub the sap on your skin.

thank you!

Can you cut all the leaves before a frost and still keep plant from dying

No. A Philodendron will die in frost with or without leaves. They're tropical plants.