i heard an answer today from R’ Elchanan Halpern Shlit”a
When they found the oil they found it buried in the ground of the Azarah, b/c a goy is considered to have Tumei Zovim – and this tumah is metamei even with just moving something. So had the oil been lying around the Yevonim would have moved it thus making it Tamei.
So we ask that maybe they did move it? we have a Klal that Sofek Tumeh nirshus harabim is tahor so even had the jug been lying around it would have been Tohor in anyway? Why did it have to be in the ground?
The Yidden planned to use an 1/8 of the Tahor oil each day and then pour in the rest of tomei oil and it would be botul (by doing it slowly, drop by drop each drop is botul). But although we say that Sofek tumeh birshus harabim is tahor it doesnt have the power to be mevatel tamei oil so it had to be buried so that there would be no Safek.
This was the nes that on the first day they found oil which there was no safek whether it was tahor or tamei
Good Shabbos