3l Gearbox

Hello to the specialists, I stopped yesterday with my 3l Lupo, built in 1999, 92000km. No more gas. Was towed by the friendly ADAC employee to the VW workshop, which had the following diagnosis ready: Some switch no longer detects the rolling lever position. Are allegedly 2 switches that have to be changed. Costs 100 Euro for the switches and 460 Euro for the installation. But now comes the best thing about the history. The workshop can not garant A wonderful statement is not true… My question to you: Has someone already experienced something similar with his 3l, or does he know what is talking about here? Many thanks already in advance!!!