The person in question apparently:
- needs to make a choice on where his next visit should be.
- has a choice of visiting Greece for this next visit.
- holds Greece as a preferred destination, given his long obsession with its temples, its rocky outcrops, and its Heraclitus and Parmenides.
- is anxious whether he will be able to spend enough/quality time in Greece if he visits this time (probably because there may not be enough time available, perhaps due to other important matters to take care of or limited duration) and he may not have a second chance to visit Greece (for whatever reason).
- is also, perhaps, anxious because he wonders when/whether he will get a chance to visit Greece if he skips it now.
For all we know, probably he has only one shot at visiting Greece, if at all, and he wants it to matter whenever it happens.
So, one of the following is at stake for him:
- the opportunity to visit Greece (should he miss it now?)
- the opportunity to spend quality time in Greece (should he visit it in a hurry?)
If something that is valuable is at stake, it is
in a situation where it might be lost: Thousands of lives will be at
stake if emergency aid does not arrive in the city soon.