I'm making a pineapple shaped cake. It 4 layers and is about 7" high. I probably put too much filling in and stupidly did not put a board in half way up and the bottom layer is suffering. Its crumbcoated but leaning. Is there anything I can do to shore it up? I'm going to cover it in fondant tiles which will have quite an organic natural look so it doesn't have to be perfectly symmetrical but obviously I don't want to have a leaning tower of pineapple.

Please help. 

I'd take it apart and add a board and supports. 

Reluctantly I’ve done what you suggested. It’s a shame because I’ve lost a layer of filling (pineapple jam and  rum coconut buttercream

You can try to secure it with dowels or bubble straws so that it doesn't slide again.  

I understand, but you did the right thing to get a secure cake.  Adding straws or dowels without a support board wouldn't do anything.  Better missing some filling than witnessing a collapse.