AFAIK, no, that's an amenity TMW hasn't yet provided with the ticklabel property. It's a very simple text string with formatting limited to what can do w/ TeX subset and fonts, etc. It's not a text box control or anything even approaching such.
It undoubtedly can be made to work but you'll have to do the line breaks yourself.
I think using the annotation "trick" with positions centered on the tick values will be your simplest route by far.
You could check File Exchange and see if somebody has already done the heavy lifting for you; if not your function would be a useful submittal.