So please tell me, 1. do these exercises improve one's health across the board and slow down aging? and 2. is this set of five exercises Tibetan in origin?https://en.wikipedia.org/wiki/Five_Tibetan_Rites
1. They are pretty basic exercises which I can't see doing any harm as long as one is careful(as with any exercise). Moving the body is good. Don't know about the aging thing but the healthier your body is the better in the long term.
2. I vaguely remember a thread on e-sangha where someone said they had some similarities and were likely lifted and modified from some kagyu trulkhor exercises or preliminary exercises, something like that.