He's ranked right about where the Oilers look like they will be picking (Around 20-22) by Button.
Button's ranking isn't necessarily a reflection of even how he thinks the draft will unfold. Button wasn't high on Jake Virtanen in his draft year, but in his mock draft Button still had Virtanen going to Vancouver at #6.
Bob McKenzie's survey of scouts is usually a better barometer for where prospects might go: http://www.tsn.ca/patrick-has-decided-edge-in-tsn-hockey-mid-season-draft-ranking-1.661533
6. Mississauga Steelhead hard-shooting winger Owen Tippett, who also happens to be the cousin of Tampa prospect and London Knight Mitchell Stephens. Tippett's range of votes was from three to 13.