Complex sentence: He assembled a team of skilled programmers, engineers and physicists, including David Sloan, who was instrumental in getting MacDonald Dettwiler and Associates into the satellite business and who had played a key role in BC's wireless data industry at Mobile Data International.
Split into simpler sentences: He assembled a team of skilled programmers and engineers, including David Sloan, a physicist, who while at MacDonald Dettwiler and Associates, was instrumental in getting the firm into the satellite business. Sloan also played a role in BC's wireless data industry while working at Mobile Data International.