There is no such thing as "indigenous science". Either it is based on scientific principles and makes use of the scientific method - in which case it is science - or it isn't and doesn't - then it isn't science.
I see no use in redefining science.
What is really the issue here is realizing that indigenous people have indigenous
wisdom. Many of their anecdotes and habits result from observing their environment and forming rules to preserve it. That's
almost science. And scientists are well advised to take those wisdoms into account. Many of them are there for a reason. Others, otoh, are simply superstitions or outdated but nobody remembers the reason they where established. That is where modern science comes in and can test and explain the indigenous traditions, to sort superstition from wisdom.
Where I emphatically agree with Dr. Pfeiffer is that it would be stupid and arrogant to ignore the indigenous wisdom.