Bro.. the RISC2 is an Egyptian System.. part of the Egyptian own C5Isr.. it has nothing to do with Russia..AFAIK there are continuous flight between Egypt and Russia carried out by Egyptian Transport Aircrafts. Initially I thought they could be transporting the RISC2 system to be installed on the Sukhois but who knows what they were actually lifting. I don’t think any Egyptian MiG-29M2s flew to Russia for upgrades since their arrival, one would question if these upgrades can be carried out in Egypt but I think the answer is no.
Why not ..if only the radar and some avionics needed to be upgraded in Egypt.. we know that Egypt don't send its systems to be upgraded somewhere else but in Egypt.. Most of the time..And that is like 95% of the time..