I'm afraid that's your call. Results like this still don't tell you
whether it is too new for all to detect or if it is a FP detection. Why
not quarantine it and check again later.
Try the free versions of MalwareBytes Anti-Malware (MBAM) and/or
SuperAntiSpyware (SAS) and see how they find it.
Both of the programs let you decide what to do with what they find.
In the meantime, you may want to change the dll extension to something
like dlk to prevent it from doing any damage.
If you decide the file is OK, then just change the extension back to dll.
I'm afraid that's your call. Results like this still don't tell you
whether it is too new for all to detect or if it is a FP detection. Why
not quarantine it and check again later.