KQ is not cashing out. The shares to be sold are 'new' shares thus diluting KQ & Shirima's stake [Note: I have no idea whether Shirima is selling his shares]
I may be mistaken but I think the idea is per @GG
1. Capital for fleet renewal
2. Involvement of (more) TANZANIANS in the airline (ownership)
Why?
1. Tanzania is HUGE. It is tough to move around the country by road so flying is popular (for those who can afford it).
2. Tanzanians are xenophobic about Kenyans. The dead Air Tanzania has been designated a National Airline & the same courtesy was not accorded to 'larger' PW. I do not know the current status.
As a National Airline, PW can access routes subject to bilateral agreements i.e. more destinations are opened.
Many Tanzanians DIRECTLY fly to Dubai, London, etc & they use BA, Emirates, etc but now PW can compete in this market. KQ will lose some traffic but OVERALL the gain is higher to the KQ/PW combo.
Another advantage is that if there is a delay on a KQ flight from Dubai-Nairobi, you can use PW from DBX-DSM-NBO instead of being 'stuck' in Dubai or being put on Emirates.
Greedy when others are fearful. Very fearful when others are greedy - to paraphrase Warren Buffett