Whole paving slabs under patio

[Jackle]

I'm in the process of extending our patio. I'm going to build a supporting wall around the outside, then fill with aggregate, followed by a concrete layer, then the slabs on top.
I've got a couple of 18" whole slabs to get rid of, can I leave them at the bottom under the aggregate layer whole or will I need to try to break them up first?

 

[Newboy]

leave them where they are

 

[Jackle]

That's the answer I was hoping for!
They've been in place for quite a while (supporting a trampoline) so are fairly settled in place...