I don't think they will let you get through the airport in Doha as if your sponsor not living here anymore and his visa been cancelled, then all the visas under his sponsorship would be cancelled automatically, this is what I think.

Lets say if it is valid, then how do you think you will be able to live in Qatar without available sponsor, how will you able to change your sponsorship or travel back without exit permit ... etc ???

My advice, don't take the risk.