Shouldn't the phase value lag the line-line value by 30°?

 

Which line to line voltage, there are 3 - 120 degrees apart? Phase is relative - a meaningless quantity without a reference phase. The solution chose and stated the leg/load terminal voltage with respect to neutral as the reference - so by their definition it has phase 0 deg. Given the stated variables in the problem I think that was the only unambiguous choice for a reference.

Also I don't know where you got the 30 deg value. From the load or are you thinking of phase relationships in line vs line to line in a delta configuration? Either way it is not relevant for reason I stated in the first paragraph and because this load is in a Y configuration.