I can vaguely remember an issue or two with drying time back before I had a conditioned shop, and it was likely caused by the humidity. We stay near 100 percent humidity outside here most of the year.
Now, in my 28-34 percent humidity shop, I never have an issue with any wood and I use them all (over 60 species on hand all the time).
You can try to put it in a warmer/dryer enviroment, but be careful. If there is excessive moisture in the wood in question, this may cause issues structurally.
Can't say as I ever mixed the epoxy without adequate time sweating in (min. 30 minutes before adding thinner) or un-even amounts of A vs. B or vice versa so I don't know what this would do. If you can eliminate this as a possibility too...we may have a mystery.
BigJim