Mass Effect 2: 10 Cut Characters You Never Knew About

Yes, BioWare intended to include an explosives expert on Shepard’s team. Presumably, this character would have been integral to destroy the Collector's base. The game would have included a mission, probably their loyalty mission, to acquire specific explosives or an explosive device, which could help the team against the Collectors.

Bioware hadn't decided the character's species, but there's a strong chance the character could have been Salaraian, as Garrus states that he had a Salarian explosives expert as part of his team. Garrus's explosive expert might be a nod to the Mad Bomber character.

As Garrus suspects his explosives expert to be former Special Tasks Group, the Mad Bomber might have been cut to avoid having two ex-STG members on Shepard’s team.