I'd have brought her in and rifled through her handbag and purse to see if she'd owt worth snaffling before turfing her back out again :-)
OK, lol, in all seriousness, no, i'm almost ashamed to say I wouldn't have let her into my house either, especially not with your child present. My grandma, before she died, suffered from dementia. Often in her confused state she would lash out and it was surprising how strong she still was!
You did the right thing, and luckily she was found safe and well.