So far, I found on one of your websites that the paid (Pro) version is only licensed for one domain. Administration of a multisite typically occurs under a single domain. So, this technically means that one license could apply to all websites in a single multisite. But, it’s unclear how reality might settle on this.
Forum Moderator and Brute Squad
For pro or commercial product support please contact the author directly on their site. This includes pre-sales topics.
As the author is aware, commercial products are not supported in these forums. As you are their potential customer I am sure they will have no problem supporting you there.