Guidance needed around toadstool substrate requirements

[nim6us]

I don’t have any experience with toadstools so forgive me if this is a daft question. I’ve got a small one in my frag QT that’s ready to go over to my display. It was shipped to me on a small piece of rubble (see pic). My question is can I just sit this down as is in the DT sandbed or will the stalk(?) need more of a base. Meaning should I glue that rubble to bigger piece of rock before placing it in the sand?

 

[JGT]

I would do the latter to give it more of a base to spread out over time as it grows.