There is often evidence outside of just written word, especially when you have around 2 million people migrating from one place to another. And the Egyptians seemed to be rather OCD when it came to recording their daily lives, and there isn't any mention of a large number of Jewish slaves, settlers, mercenaries, or others. And the fact that their languages did not change during the "enslavement" also reduce the likelihood.
Twin bombs kill around 10 and wound 100 in Cameroon town (Reuters)
from the article: Were Jews ever really slaves in Egypt, or is Passover a myth?