Hi, I'm Robert and I'll be helping you with your printer question.
I think I have the same printer give me a minute to look at it please
I have a similar one and there are 2 gray insets that you have to squeeze together then pull straight out.
Do you have a duplexer. That would go in the same place and make it different to open
i think that you just have to make sure that you squeeze both of them all the way to the center. then pull it straight back
there may be some paper stuck where it needs to release the catch
but i would think that you can get it by pushing harder or jiggling it or maybe a thin screw driver if you can get it away from the body enough to slide in
i put up an offer for the phone call but the site requires an additional charge. i put it up at $20 which is about 50% less than the site usually wants.
i can keep helping this way. for the phone call you have to accept the offer.
if you have something like skype on a tablet or phone i can do that as well and see the printer through the video feed.