1st off. did what you saw look effective?
Did they seem serious?
Did you get a good vibe from the instructor?
My Sesnei started at the Trimont Dojo, in the Soth Bronx, under Antonio Perrara, and it was a Jujutsu,Judo and Karate school, my Sensei studied Judo and Jujutsu together, competeingin Judo and studying Jujutsu for the streetfights common in his youth,and he did fine as a cop with it.
I have to disagree that Judo Jujutsu should not be studied together, it is actually an advantage, many Jujutsu techniques should not be used in sparring (That's true of every art, even Boxing has rabbit punches, just cant use them in the ring.) Judo randori gives you a rule set to limit injury, so you can go all out with an opponent, this is very valuable, especially if you have not been in many nasty fights.
Judo and Jujutsu go together, when I do Judo rules Randori, I dont use arm break, head thrwos and other Jujutsu goddies, and they dont happen even underf pressure.
When I have fought, I always go toward the nastier stuff.
Now if this Sesnei is older, there is a good chance he has studied Judo,Jujutsu, Aikido,Ninjutsu and Karate, he just might have more time with 1 or 2 arts than the others. We do 2 main arts at our Dojo, but lots of us have done other arts, so allot of crosstraining goes on, you might walk in and see someone enter with a FMA strike combo, use a Jujutsu head manipulation and end up using a Judo pin, to punch the downed opponent in the face. I digress, if the instructor is under 30 and claims profficeintcy in all the above arts, make like an Iron Maiden song and Run to the Hills.