Hello, Ginger Snap! I'm sorry to hear about your bad experience, I suspect it's the same teacher whose classes someone I know walked out of and also lost her money. A case of flashy advertising and good, old fashioned bullsh*t over genuine experience and ability, I fear.
The only teacher I've been to in North London is Shafeek Ibrahim, an Egyptian who is a fantastic dancer and teacher.
"Based in London Shafeek teaches at The Place dance school in Euston. Tuesdays 6.30-8.30pm studio 6. Classes are usually drop in classes, but also can be pre-booked"
Shafeek Dance
There's also Jo Wise, although I haven't been to one of her classes:
http://www.jwaad.ndirect.co.uk/