Humalog is supposed to be refridgerated(as with all other insulin). And 25 days is alot of time to have insulin not cool. Plus I'd be willing to bet that the summer heat isn't helping any. But I have seen stranger things happen before. The only way you'll find out if it's bunk is to use it. I don't see any harm in trying it out...
Humalog actually doesn't need to be refrigerated UNLESS you plan on storing it for any extended amount of time. People with insulin pumps are quite aware of this. For general storage and use if you're not going to use it within a month or so you should keep it refrigerated as much as possible.
As to the above situation- it could go either way depending on how hot it got etc. 25 days is right at the borderline in my opinion and I would tread with caution.
once humalog is opened you can keep it 28 days out of fridge up to 28-30 degrees if im not mistaken. only needs to be stored in fridge and once opened doesnt need to be kept in the fridge. 25 days out though?
I would say no but have not enough personal experience to say for sure.