I agree that the fence could be your fault, make sure you are doing one or two passes around the edge of the property to keep the clippings off the grass.
The grass not growing is 100% the clients fault assuming that you seeded, fertilizer, put down penn mulch or straw, and told them that they needed to water every morning before noon for two weeks and then could go to every other morning for another two weeks.
There is an Old Blue Chair for each and every one of us, we just have to find it.
2006 GMC Sierra 2500hd crew cab
BOSS 8'2" Power V
Hustler X-one 60"
Toro Proline 36" wb w/t-bar controls
JS46 22" walk-behind (wouldn't recommend)
Shindaiwa T254, Echo trimmers, chainsaws, pole hedge trimmer, pole saw, hedge trimmer
Shindaiwa 633 and Husqvarna 130BT blower