Can gold cause tin or other metals to corrode?
First off, read carefully:


  Different metals will increase the likelihood of corrosion.


It doesn't say:


  Different metals will increase the likelihood of corrosion of gold


With that in mind, it's called galvanic corrosion and occurs when contact between two (or more) dissimilar metals causes the more reactive one to corrode when it normally would not have or faster than it would on its own. This action is similar to a galvanic pile (though its only one cell) that has short circuited thus corroding the more reactive metal.

In your case it is definately the tin that will be corroded, not the gold as tin is more reactive.