churned up lawns from heavy useage

The lawns where I work have got very churned up over the last few weeks from a ride on mower with trailer (at this point I have to mention the garden is getting a complete make over apart from the lawns). There is only one way to get to the bonfire in the back garden so I can only take that route time and time again thus leaving mud pathways where once was grass. I have tried using carpet, sawdust, wooden boards to minimise the wear and tear of the area but it doesn't help. I cannot slab the areas either. The owner has a wedding there in August and I don't want this being an eyesore for them. Anyone got any other ideas or tricks I can use? TIA