In regards to testing if a module you are utilizing is secure or not there are several routes you can take. I will touch on the pros/cons of each so you can make a more informed decision.
Currently, there aren't any vulnerabilities for the module you are utilizing, however, this can often lead to a false sense of security as there very well could be a vulnerability currently exploiting the module/software package you are using and you wouldn't be alerted to a problem until the vendor applies a fix/patch.
To keep abreast of vulnerabilities you will need to follow mailing lists, forums, IRC & other hacking related discussions. PRO: You can often times you will become aware of potential problems within a library before a vendor has been alerted or has issued a fix/patch to remedy the potential avenue of attack on their software. CON: This can be very time consuming and resource intensive. If you do go this route a bot using RSS feeds, log parsing (IRC chat logs) and or a web scrapper using key phrases (in this case node-mysql-native) and notifications can help reduce time spent trolling these resources.
Create a fuzzer, use a fuzzer or other vulnerability framework such as metasploit, sqlMap etc. to help test for problems that the vendor may not have looked for. PRO: This can prove to be a sure fire method of ensuring to an acceptable level whether or not the module/software you are implementing is safe for public access. CON: This also becomes time consuming and costly. The other problem will stem from false positives as well as uneducated review of the results where a problem resides but is not noticed.
Really security, and application security in general can be very time consuming and resource intensive. One thing managers will always use is a formula to determine the cost effectiveness (manpower, resources, time, pay etc) of performing the above two options.
Anyways, I realize this is not a 'yes' or 'no' answer that may have been hoping for but I don't think anyone can give that to you until they perform an analysis of the software in question.