Translator here. They do make up stuff or omit stuff they don’t like. Machine translation is fine for tourists or to translate a ikea manual in the wrong language. If there are stakes, risky. They got good enough to make sentences that look right so it can be tricky to spot the errors if you don’t pay attention.
Numbers are typical errors. Sometimes it’s there but the number has changed. Sometimes it’s not there at all. Oh and if you have currencies a translators knows a document from the UK in pounds that is adapted for France will have to be converted in euros. Machines don’t.
Generally speaking when a client wants to use machine translation, it costs them more money in the end because of the extra time needed to correct everything to a high human grade standard.