Not without a weird angle and I'm not sure there. Certainly not flat. The VIP lounge chairs do not fold completely flat. You can move them forward, and angle them some. That gives you roughly 86 cubic feet of space. If you want maximum cargo you will need to go with a lower trim that let's you remove the middle row. I've seen images of those with plywood. Assuming you mean 4' x 8' plywood.
I haven't tried it but you may be able to do one of two things:
1. Slide the chairs all the way outward and angle in a 4x8 - If it fits, this would be your best option
2. Lean the chairs all the way backwards (they nearly go flat) and lay the plywood on top. Not sure if this would be advisable because of the load and stress on the seat backs from the weight