I can confirm this bug exists.
On April 17th 2015 I took a screenshot of a suspended user’s public profile with the specific reason “Use of multiple accounts detected”. The user was at that time given a many year suspension until the year 2289.
I’ll have to hide the username and other content but this is what it looked at the time (April 2015):
And this is what it looks like now:
Additionally in the admin section the reason is not shown:
This user has been suspended once, no other action has been taken against this account.
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