No, it's not a rebuke of Uriah for fleeing to Egypt, or even a commentary on Uriah at all. Rather, it's about the hardness of the king. The point of the brief account is to show the extent of King Jehoiakim's refusal to listen to God's prophets, revealing how much danger Jeremiah faces in the larger passage. The king is so hostile to true prophets that he isn't content with having forced Uriah to flee, but pursues him all the way to Egypt in order to kill him and dishonor the body. No blame rests on Uriah for that, but much rests on the king.