Hi Sonika,

It looks as though your message was posted in April? but I think it's more recent?
I'm not sure about Namibia, but have you thought about South Africa? please have a look at this web link for an 8 day tour called Africa Enabled which is based around Johannesburg and designed for wheelchair users and their families.

http://www.kumuka.com/South-Africa-Enabled.aspx

The tour starts and finishes in Johannesburg and includes Kruger National Park with the big 5 animals (rhino, buffalo, elephant, lion and leopard) plus a wide range of antelope, small cat and bird species. Scenically it's a very interesting area - with a number of rivers and dams which make excellent places to watch and wait for wildlife. The tour also includes a stay on a private game reserve and visit to the spectacular Blyde River Canyon.

Good luck with your travel plans,

Jane