Until Fiverr changes the buyer request page (maybe to allow flagging) couldn’t moderators send a message to all those spamming the buyer requests (or totally incorrectly entered buyer requests), ie. the same message to all of them, asking them to remove their buyer request, telling them that spamming buyer requests is against the rules? Maybe if they haven’t removed them within a certain specified timeframe, maybe the mods could remove the requests (if they have that ability) or maybe the user could be suspended for a short time - if they’ve spammed that section and they haven’t removed it within the timeframe (and that could be specified in the warning).
Another option - maybe some sort of browser plugin (or program) could be developed (unless it would be against the rules) to find the actual buyer requests (ie. excluding all seller adverts etc) within the buyer requests section :).
But also, the section where buyer requests get entered could also do with being changed, to make it easier for valid requests to be entered (eg. it should tell the user what exactly is wrong with their request if it is refused).