How can I introduce two female robo hamsters? 'read more'?

[éNDLéR GúPPY]

One of them died (It's a long story how...) It was not of a disease but an acident how she died (I didn't kill her...)

Anyway, I have three hamsters.

Two males

One winter white.
One cambell.

One female
One roborovski.

My roborovski hamster Biscuit has been alone for five days now since her sisters death. I've only had for about four weeks. I found out her old sisters are still in the pet shop ( Three sisters ) So I was thinking because her sister Honey died I might be able to re-introduce them? I'd only want to get one of the three sisters. I read is shortens their life span if they live alone and they are very social right? I was thinking because the sisters haven't be alone from other hamsters nor has Biscuit... I might be able to introduce them over a few days?? I am making a bin cage because their old cage (Giant rabbit cage) Was too easy for them to escape from...

Could I re-introduce them?

If too many people think I can't, i'll probably get no more hamsters or a White chinese dwarf...

Thanks<3