Yep, there is no orange moddable techblade even when there should be one based on all other rewards lol.
I suspect the reason there isn't is due to the fact that barring it using a barrel instead of a hilt you'd never be able to find an aim hilt to put in it. Then again at least they could have made the mod and enhancement slots moddable still. I dunno, BW really screwed the pooch when it came to Qyzen's itemization/stats. They may have had legitimate reasons for taking the route they did, but it's still just caused more problems.
Troopers have a companion that uses a techblade with aim primary stat also (IMO he's the best companion to use for a DPS or healing commando). So it's not like this is a unique problem.