Hey, William.  I appreciate the update! 

Artists do indeed reuse licks from those that influence or inspire them.  It's how they use them that gives them a unique, individual & identifiable style.

SRV is a great case in point.  I don't think he ever played a single lick or series of notes that hadn't been played by blues players before him.  You can find the licks he did in the recordings of Lonnie Mack, Johnny Winter, Buddy Guy and all the blues Kings.  But what made him unique is they way he put them together, the tone, the touch, and of course his own rhythmic phrasing.

The lesson here is that you should work on playing or making up riffs and licks that sound like good music to you.  Things that sound cool.  And any originality you find along the way will follow as result of that process.  If you set out with originality in mind as a goal, then you are almost guaranteed to fail because how can you be sure what you played hasn't been played before?  Or that maybe you heard it somewhere before and now you have to figure out if it's completely original or not?  Or just partially original and you might have to adjust the part that was too unoriginal?  And that's just the guitar part.  There's also the bass, drums, the overall song arrangement, and so on.

Just try to play good music.  That's challenge enough!

Regarding the computer program you are using, you have the right basic idea.  It's formed from an input of a large database of existing music, then it uses that as the basis for output based on user input.  I doubt it explicitly copies some existing song's riff.  But I wouldn't be surprised if some output resulted in randomly generated a riff or lick verbatim.  If you tell it you want a blues-rock riff, there are a lot of possibilities but the overall parameters for what would be considered appropriate are programmed to fit well within that genre.

Keep practicing!