Hiya Kat,
i am very sorry to hear of your loss - it must have been very upsetting for you to find them like that
I get asked similar questions al l the time - 'why have my robos killed each other?' - but the fact is that Robos will not usually fight for the death and will not usually kill each other - it is very rare!
In the wild they will fight for dominance and the weaker one will leave the territory to the stronger, more dominant one - they probably dont even cause that much damage to each other in the wild - the probably sort things out with squeaks and boxing etc.
The problems with captive robos is that they will have their little arguments with squeaks and boxing and the least dominant one will run off, but then he / she will have to face the dominant again, and then again - and soon the dominant one will get sick of trying to frighten the weaker one off and will then attack - obviously this is not either of their faults - they cannot get out of the cage / territories
The attacks gradually get more ferocious and serious and eventually they will cause a wound which is serious enough to cause death - they do not usually kill each other, but they can cause wounds which can cause death
- and yes, once a hamster is dead, the others will try to dispose of the body to prevent predators from being drawn - that is just a natural instinct
So usually, there are signs which you must watch out for with any hamsters who are living together - squeaks, boxing, bullying, individuals being prevented from eating or drinking, wounds (slight at first and then more serious) etc. If you catch these warning signs early you can sometimes prevent serious fights or wounds.
i hope this helps you for in the future
Tammy x