Boiled linseed oil can promote mold and mildew growth. It can act as a food source. Don't bother with epoxy. It's a waste of money and I don't think it will make much difference. I would recommend going over the frame with a bleach solution to kill any mold spores in the wood, and then go over the frame with light pine tar, which is an antiseptic. It's really not that exotic, you can find it at a shop like Tractor Supply that carries items for equine care. They use it on horses' hooves to prevent infection. I'd put on two coats and let it dry in the sun, then any place that is sticky where you think it might be a problem I'd go over it with linseed oil. Otherwise just don't worry about it. It will be really difficult to get it to dry between the skin and the wood, so if you're paddling fresh water I'd swish around some bleach or salt water in it from time to time.

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