Noreen,
Aye, I would assume so. Can't figure why he'd be depicted in photos with a piano accordion if he strictly played a button instrument. I imagine a lot of accordion players use both. There seems to be varied opinion as to which type of accordion best suits "Celtic" music. Myself, I enjoy either, tho I can't play them. I simulate accordion on my digital piano when I attempt to play some of the "auld Scotch sangs" I love so much.
Cheers
ScottyG