Nope - still can't get my head round that photograph. I can see a part of the current building which resembles it - but that would require an extension to have been built on to the left after your photograph was taken, and that would probably make your photo much earlier than 1954. Basically, the slope and drop of the roof just look wrong to me.
Had a search online, but there are very few photographs of the place online, and none of them help.
My suggestion would be to see if the library or Highland Archives had any old maps or plans. However, most maps will show only the shape of the building, and I don't think OS maps ever showed bell towers (as opposed to "church with spire").
The firm which converted the orphanage and built Drynie Terrace was called Campbell's, and I think that they have long since disappeared. It's a very slim chance, but maybe there's an archive of their stuff somewhere...