Wet cat food is food for consumption by cats.
Cats have requirements for their specific dietary nutrients.
Certain nutrients, including many vitamins and amino acids, are degraded by the temperatures, pressures and chemical treatments used during manufacture.
They must be added after manufacture to avoid nutritional deficiency.
The amino acid taurine, for example, which is found within meat, is degraded during processing, so synthetic taurine is normally added afterwards.
Long-term taurine deficiency may result in retinal degeneration, loss of vision, and cardiac arrest. (source)
So can hamsters eat wet cat food at all?
No they can’t at all.
Wet cat food is made only for the specific nutritional requirements of cats, and so is a food to avoid feeding hamsters.