He should speak to you before closing it as Spam ESPECIALLY since it was a "RDM" report NOT something such as "He stole my cookies" or similar, So it wasn't spam and you wanted it to be handled not reported as spam I'll support this
Sorry I couldn't help you in the RP house KOS sign situation but honestly That RP house lagged me to shit and I honeslty didn't know if it was allowed or not as I don't see it stated in rules