I agree with her. What kind of support is it that your DC needs and how much?
Maths worksheet? Tell them to sit in front of it for 20 minutes and really try and think and have a go. If nothings written in 20 minutes write a note explaining to the teacher that it was attempted and they could literally do none of it. If it's all wrong the teacher will see it's wrong. Whatever they do, send it in.
Make a project about Ancient Greece? Do they have means to research? Basic art supplies? I'm sure they could come up with literally something alone even if it's not as good as you assume it's supposed to be. If all else fails, google a picture of the Olympic rings for them and tell them to draw them.
Allocate the amount of time you feel appropriate, direct them to the supplies available to them, if any. Chat with them about ideas on trip the journey to / from school. Then send it in.
If all they do is take their shoebox and draw a football on it then send in the shoebox.
If they're writing a story and they write "once upon a time there was a boy the end" then send it in.
I really don't understand the whole "homework for them is homework for me" thing. They can only do what they can do. If they're not capable the teacher needs to know. The teacher does not want to mark 20 essays about endangered rhinos written by adults.
Homework shouldn't be about extra teaching by the parents. If should be practising what they've already learned or using their research skills or creativity.
If they can't even attempt it alone because they don't understand the content then the teacher needs to see that and urgently.
If they can't do any because they "can't think of any ideas" then chat and suggest ideas on the journey home. Come up with the simplest most boring idea and if they can't think do anything tell them they can use that.
In my experience, the things parents say the kids cannot possibly do without hours of support are things they do in the classroom every day with no help whatsoever. At home they're just more scared about doing it "wrong".