Gee whizz. This guy calls himself a finish carpenter? I don't think so. The angle might not be a perfect 90 degree angle but he needed to determine what the angle was and miter the cuts accordingly. The two ends of the base shoe should butt up to each other.
Even the other end doesn't look good to me.

This is something that I would have redone. It's NOT acceptable.

thanks, Mizzou75. It looks awful and I'm insisting it be fixed. Actually, it looks like it was chewed off not sawn!

Try using a piece of trim a little taller and slightly wider than both of these but with similar shape (rounded at the top). Cut two of them with miter for corner and 90 degrees where they meet the current trim. I would cut these both back at about 1/2." The corner trim pieces would each be about an inch long.

The image I attached is to give you an idea even though they are on different levels.

Assuming same size molding on both sides ... a miter joint that is not 45 degrees would work just fine.

Thanks, msmi.

Small rant here: I think it is unacceptable that I have to go on a forum like this (not that I don't appreciate all that these forums do for me and others) to get an answer to this problem. Either the finish carpenter or the construction supervisor or the GC ought to know how to do this, instead of the crummy job they did!

LG, I too thought they could just miter it using a different degree of angle. But when I suggested it, I got some falderol about why it can't be done. I would love to tell you what they said to me, but it was so non-sensical that I couldn't follow it. What I heard was "we are lazy and don't want to take the time to it properly."