Doc is reasonably sure that he consulted on the security design for DIMR, or hacked DIMR, or did a run against DIMR, or otherwise acquired a complete and thorough understanding of what DIMR does for its corporate security.
Ace's Security Tactics roll is also excellent, so between the two rolls you have a good grasp of what they would do.
From previous Matrix research, Doc already knows that the DIMR is in the UCAS sector of Denver. I'm not really sure how to apply his glitch, or if it matters. Almost any conceivable error he could make could be easily corrected by Ace or by the Matrix.
Also from previous research, Doc knows that the DIMR's presence in Denver is a modest regional office (~350 employees). DIMR shares space in an office building with the Draco Foundation and the Astral Space Preservation Society (ASPS). While technically one building, it might be easier to think of the building as two connected towers. The two towers (~7 stories each) share a lobby and reception area on the ground floor. The Draco Foundation has one tower (the south one) while the DIMR and ASPS share the other tower (the north one). There is a parking garage under the building. The building is a sleepy suburb, surrounded by apartments, condos, and other similarly modest office buildings.
Because they share the same space, the organizations can pool their security resources. Doc strongly suspects that the Host rating would be 6, the Firewall rating 9. Because of the ASPS, the organizations collectively have a strong relationship with the spirit world. They even employ Free Spirits, sometimes for security. Astral security will be a nightmare.
Physical security is where they will be weakest. That's not to say weak; it just won't be the horror show of the astral and the Matrix. In addition to professional receptionists and security guards in the lobby, Ace thinks they will have a small (~8 person) HTR team available at all times to respond to physical intrusions, capable of splitting into two teams of 4, with another 1-2 HTR teams on-call that could arrive within 10 minutes if things get out of hand. The astral security (spirits) may be used to supplement the on-site HTR team if necessary.
Walking in and getting an immediate meeting with Jessica Jäger isn't going to happen unless you get lucky. You'd have to talk your way past reception into speaking with someone who can assense the quicksilver photograph. That person would then have to believe that you're worth dealing with and that Jessica should be bothered. You'd also be taking the risk that they wouldn't just bop you over the head and try to magically extract the location of the artifact out of you. That's what Ace would do, but this is the DIMR and not Ares. It's unlikely that they'd do that, but do you want to take the risk? You'll be outnumbered and on their turf.
As for sending a non-assensable copy of the photograph to Jessica in advance, it's unclear whether that message would get to her or her secretary, and that a non-assensable copy would be intriguing enough to clear time on her schedule.
Let's roll to see how many good copies of the quicksilver photograph you have:
Quicksilver Photography (defaulting):
5d6t5 3Katsina's an accidentally good photographer. You have three good copies to work with.