Curators can definitely still view suspended profiles and unsuspend users. Did they give you the correct username? If it was flagged as spam, it won’t appear in the header search (even for curators), but you can still navigate directly to the URL of the profile page. From there you can unsuspend them and/or mark as a non-spammer.
There is an automatic anti-spam process on iNat (Akismet) and I frequently (several times a week) have to unsuspend normal users who were accidentally caught up in it. Not sure if anyone else is looking out for these but I know I’d personally be pretty demotivated to participate if my account were suspended for no reason, which is why I spend time trying to fix it. See related topic https://forum.inaturalist.org/t/false-positive-spam-flag-resolution/1343