DMP Answer

It's pretty certain that you must hit with the 4.  Most people make the mistake of bringing the two in from your bar point to get another cover for your blot.  There are two reasons it is better to bring the two up from the 24:  first, it makes it easier to get that checker out if things go well, and second, if you strip your bar point and roll a 4 to cover from your bar point, you are giving up your bar point or leaving a blot there, and that is a very critical point to hold.