Molded....."to form into a particular shape; give shape to"....like from a 3"X3"X60" block of plastic resin, fiberglass, lemonwood or hickory. Thousands of early wooden and plastic bows were "molded" under this definition.
Look closely at an early hickory Pearson flat bow and the first thing you notice is the violation of grow rings on the back. No attempt to follow a growth ring, just sawn into a rough form and finished up.
The billet was sawn into a rough form of the bow design; cleaned up with files, sanding, etc., and final finishing. The plastic/fiberglass bows weren't highly finished.
A couple of things noted. First, you have apparently made up your mind this bow is whale bone. It might very well be and you could easily have determined that with a little effort, but choose to post it here using only "hear say" to valid your position.
The easiest method to valid or prove existence or authenticity is attempt to dis-prove it. That's the best method in dealing with history IMO. The reason is certain things cannot be easily validated or proven. If you cannot "dis-credit" the item or issue, it lends weight to it being authentic, even when it cannot be validated. Kinda' like that old "shell game." If you raise two of the shells and the pea is absent...the pea must be under the remaining shell.
If the bow turns out to be from whale bone, its pretty rare, if not.......you should have been able to figure that on your own.