Why would an EEG show abnormal sharp spikes with strange behavior but not read like a seizure? We suspected seizures, what else could it be?

Need correlation. First, contact the reader of the EEG and inquire as to the significance of the "sharp waves". Second, ask your neurologist what might be causing the "seizure activity". Third, if there is suspicion of epilepsy, your best comprehensive approach is a 3 day ambulatory study.
EEG not seizure . Seizure disorder is a clinical diagnosis . EEG is only corroborating. Upto 15 percent people can have sharp waves without seizure disorder.