One report says h. pylori and high grade dysplasia in stomach and second opinion says nothing not h. pylori or even inflammation . is this common?

Not common: Although pathology can be subject to interpretation, including the presence and severity of dysplasia, the finding of h. Pylori should be straight forward and can be confirmed by immunostain. Since the implication of dysplasia is very important, i would advise another opinion on your pathology by a GI pathology expert who can reconcile the two discrepant reports.