Something similar has been discussed a few times. There's a mambot called rokmember or maybe rokaccess now that you can use for this purpose. You would put it after the jReviews comment plugin in the mambots list so it gets processed after jReviews. And then you would add the correct mambot tags in the jreviewcontent.html template or other templates used in content to hide/show info to certain groups only.

There's a setting for this, no need to do it at the template level. It's in config settings, reviews tab:

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