Yeah the family is pretty unique for not relying on mycorrhizal fungi but it does still rely on other fungi like Serendipita indica which is a basidiomycete fungus and acts as a facultative endophyte. Meaning it can live on its own in the soil but it can also develop inside plant roots and play many of the same roles mycorrhizal fungi play.

It's actually at the center of a lot of research attention right now for its potential to act as a booster for vegetables that DON'T make traditional mycorrhizal associations

What the...

That's like hearing some mammal babies don't consume milk!