Just spray it with weedkiller, then strim it all off 3-4 weeks later, rake over well, remove big stones a d if the surface is good enough, just grass seed on top with a bit of extra topsoil raked in.
Digging all that is just looking for extra work to keep yourself pontlessly busy and opening the soil to new weeds which will make the area horrible to deal with
stefan995, Can I just repeat again do insist on it in writing then if they try anything you can say you have permission if you don't get it you could find you have to put it back to as it is now and all your hard work would be a waste.
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Digging all that is just looking for extra work to keep yourself pontlessly busy and opening the soil to new weeds which will make the area horrible to deal with