Complex sentence: Mark was a creative partner in NEXT entertainment and was the first person to pitch "The Bachelor" to ABC, though he credits his business partner at the time, Mike Fleiss, with the idea itself.
Split into simpler sentences: Mark was a creative partner in NEXT entertainment (The Bachelor) and in fact was the first person to pitch the program The Bachelor to ABC. Though he credits his business partner at the time, Mike Fleiss, with the idea itself.