Definitely safe, I saw an article a couple of days ago about how drinking a cup of mimosa hostilis tea helps to assuage cigarette cravings. What that says about effectiveness is another matter... then again, I doubt the ex-smokers are making tea out of 30g.
And like was mentioned before, just making a weak ayahuasca for a soft first time is probably a better idea than using 30g of mimosa for tea.