Good idea. Sit outside with the chicks and let the hen come around and see all of you. It may take her some time to warm up. Integration can be stressful for all. Once the chicks get older it may be easier, but letting her get used to them isn't a bad idea.
Oh, well, yeah - she's not liking being invaded. She's not a Mommy Hen, she's not going to accept chicks if she's not broody, so you'll have to be patient and go slow with integration.
It might be the cage she's freaking out about? Hard to know...you may want to put the cage outside where...
Is the hen actually broody and she hatched these chicks?
How much space does she have and how did you introduce those chicks?
Adult hens that are not broody do not really like chicks all that much - or that's the way my hens are.
Sounds like your hen overheated and stressed out - I would...