Well, it can be done what is need is:
- A more violent March of Rome, basically the King call Mussolini Bluff and sent the army to arrest him; this lead to a more confused political situation with a lot of violence between socialist, fascist and the goverment, so Italy is occupied with internal matter
- some crisis who occupy the attention of London ( maybe a communist Russia is more succesfull in Poland or the communist regime in Hungary survive, more delicate internal situation etc. etc)
- Ataturk die in WWI
- Violent popular uprising in Cyprus
- Lot of ethnic cleasing done by Greece
With this and some luck there is a good change that the OP can be achievied...for three or four months, later Greece due to ecomic exaustation, scarcity of men and resource for the army, overextension and some very pissed off power (expecially Italy) is in trouble, big big trouble