In their defense, they’re understandably terrified by the Null. Even if they do not consciously realize it, they’re acting as a threatened animal, seeing the Null as their predator, which it pretty much is. Not that their attempts at getting rid of the threat would avail to anything, besides putting them on both Phil’s and the Japanese agent’s sh*t lists.

From their perspective, Phil is an eldritch horror that crawled from some dark void somewhere. He shouldn’t exist, and the fact that he does poses a very serious threat to any magical entity in the world. So it makes sense that a guardian entity (even localized like it is) would be terrified on the Null, since Phil has the potential to then erase the dragon with a thought. I cannot fault it for wanting Phil destroyed.
That said, Phil is luckily a good person, so it does come across as an ill-intended dragon spirit.