I don't have kids.. so take this with a grain of salt.
Your H is responsible for his own feelings. IF he feels you threw him under the bus.. that's because he is not ready to deal with the consequences of his actions.. or his truths.
That's on him and you shouldn't worry about protecting him from it. That's not loving..
Nor at the same time should you worry about him hating you. Try not to give him a reason but understand that because there are such crazy emotions for both the LBS and the WAS.. hatred/anger can almost always be found.
However - she is 4 and I'm not really sure what good your response did. 1 - Unless H's parents don't want to see you (sorry I don't know if that is the case) then it shouldn't matter what your H thinks or wants.
And 2 - you don't really know what H feels completely. Making a statement like that without understanding why really can do more damage that good.
What about this response next time.. "I don't know sweetie.. maybe you can ask Daddy next time you see him". If she REMEMBERS.. she will.
M(f): 40 D'ed: 8/12
Show empathy when there's pain. Show grace when warranted. Kindness in the midst of anger. Faith in the face of fear.