I am sorry but I do not understand still, what do you mean it is not recommended to have the same floating IP on the switch infrastructure and LTM? IP gets used only once on one single device I can't put the same IP on two different devices. So you are saying that since I already have VLAN5 SVI on our cores I should not be using that. I'll need to get two complete separate VLAN's lets say VLAN20 and VLAN30 and not create the SVI on the switch just add them to the VLAN database.
Next on the F5's create VLAN20 and VLAN30 and assign the interfaces to them and connect them to switch access port on the respective VLAN's?