I'll echo a few others: Why not? My first instinct would be to go with it. They do the ritual. The party knows where the MacGuffin is. The adventure is in going to get them.
Alternately: Why do scholars have to be powerful ritualists? This is D&D 4e. Nothing has a level unless it's a threat to the PC's. They're scholars and sages, not adventurers or heroes. Unless you've attributed some great magic to their working already, they can just be non-statted nothings, and thus not be able to use any kind of ritual ever for any sort of reason.
The second is a valid point that I am/was not qualified to make. I, myself, have
very limited experience with 4e.
I suppose it goes to the game in question. Namely: How prevalent is "magic" in your world? AND How rigidly do you ascribe to the RAW?
That's something only you, as the DM, can answer...and adjust in whatever ways you allow yourself
and think are FAIR to the PCs!
To my experience in play (not just as a DM of my own, but also playing in others' games), maybe it's a decidedly pre-4e conception, imho, that a "university of sages" would NOT have
some magic available to them.
And from a "popular culture" perspective, as a player, I would be envisioning something akin to the Harry Potter world/Hogwarts school. So some basic divination/scrying wouldn't seem or feel "out of place" or unreasonable to me.
I'm still reeling, I think, from the idea of "scrying" being a 24th level ritual! lol. I know, I know, levels in 4e are very different from what I am accustomed to/experienced with. "Rituals" in general are something I do not have a firm grasp of (versus "spell" use, I mean). "Locate Object" was a 3rd level clerical spell, iirc. "Is there a 5th level cleric in the house?!" lol. How about a 5th level mage/MU/wizard with "Clairvoyance"?
But again, that's just me. In 4e terms, sounds like you are completely justified in saying "no they can't do that."
However, to reference my previous post, "No you can't" doesn't have to be the tack. Some "in game, in story" reason should be offered to
describe the 'why' they can't and maintain story/game/play immersion.
When my (and I don't think I'm alone in this) "suspension of disbelief" is disrupted it is damn difficult to get back into it. It lends itself to the thinking (not saying it
would happen in future situations, but the thought is there) "Well, we can't ask for help...cuz it'll just be a..." or worse (imo), "...Rulez sez 'No'."
Again, good luck, have fun and happy gaming.
--Steel Dragons