The event horizon telescope have early results, but the seem to be busy adding VLBI stations at the moment (that's what they put on their homepage anyway).
Here is an oldish lecture about it:
We are concerned with the intermediary gas, but not with respect to seeing. The effect of interstellar gas basically distorting the spectrum we observe, calling the "reddening". I guess there could be seeing effects from the interstellar gas, but we are pretty far from that beeing a real...
To be overly explicit, a spectrum is exactly an image of the different wavelenghts from some source. It does however not make a picture in the sense that you have any spatial information.
If you want unbeatable look-back times you got to go for pulsar timing arrays, they should be able to directly detect gravitational waves from around inflation.
I would suggest you find the homepage of some recent conference on the subject that interests you and brows the talk slides (if there are any) to see what is happening.
Also, realize that what you end up do is most strongly decided by what the good advisor is willing to do. And what they are...
As I recall Einsteins General Relativity admits solutions that form closed time loops, so strict adherence to causality must be imposed by some other means.
And within the realm of Quantum Mechanics there is the eternal quest to inject determinism into (for example) the decays of states, thus...
You can probably describe this with the ideal gas law: PV/nk_B = T, since the cylinder volume is fixed, the decreasing pressure P means the temperature T in the cylinder must decrease also.