Might be time to tell them since they set up their own funky *ss system that is so abnormal from what 99.99% of other people do when setting up a network that they should figure it out for themselves...
...either that or you need to charge them some booookoe bucks per hour to figure it out for them.
Here's a few links for some valuable resources for your client:
Amazon.com: networking for dummies
Amazon.com: networking for dummies
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