I would say, based on the picture, that there is no long term structural concerns.
I'll also add that the piece seems to be a more rustic style and things like knots and so forth are part of the pieces character. Pine has a lot of knots. Look how many branches a Christmas tree has.
If it was a high end piece from a custom furniture maker then I would object, in your case I think it may be a bit un-called for. That said, see what the company says and does. They may give you some options.
Actually, looking at the picture again, I'm not sure which crack you are referring to. The crack that looks white would be the one I object to. It looks like it was filled with something that didn't take up the stain. I would want that colored in to match. Just a brown sharpie marker will do that. The guy from the company will probably have something like that with him, have him do it. All the cracks are structurally okay.
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