What should Trump do? Arrest a bunch of rogue judges? Got any solutions?
I’d advise Trump to simply disregard judges when their rulings are clearly unconstitutional.
Your question should be: what should Congress do? Answer: they should tell Trump what to do, because that is their Constitutional duty, Trump is just doing the same as he always does, respecting the Constitution, and following the law the best he can considering the law is not prescriptive. As for the judges, appeal them and wait for sanity at the USSC. The USSC will obviously point out the law requires arrest and deportation, the executive cannot ignore that law, and they especially cannot carve out an entire class of exceptions to enforcement.
A nice thing about Trump is he always respects the balance of power and is in this case as in many cases throwing it back to Congress where it belongs. If they fail, then the highest court will tell him to enforce the law. Then he will have no choice, whether he likes dreamers or not.