DO NOTHING, Sundance says it is a "maintenence free" cabinet. Use something on it and if something happens to it, it could be said it is because you used the "wrong" stuff on it. Refer to your owners manual where it will remain silent on this issue, which is what the manufacturer seems to be saying, "do nothing".
But then of course, you can follow the technicians advice but see if he will give it to you in writing in case you run into a problem in the next two years.
The cabinet is very durable and you should not concern yourself with this issue of concern.