Hi Esha,
we are not entitled to speak for PMI or Pearson VUE. So I would recommend to contact them directly (preferably via e-mail, as I know the waiting time for the chat support may be quite long) in order to be sure whether a dongle connection is allowed.
I can only refer you to requirements specified on their website. Specifically to your question, while a wired network is recommended, wifi is not prohibited.
Here is what PearsonVUE specifies on the website regarding the internet connection:
For optimal performance, a reliable and stable connection speed of 3 Mbps down and 2 Mbps up is required.
Where possible, we recommend testing on a wired network as opposed to a wireless network.
If testing from home, ask others within the household to avoid internet use during your exam session.
Tethering to a mobile hotspot is explicitly prohibited.
Further details are available at the following link:
home.pearsonvue.com/pmi/onvue
Gabriella