[OldRestorer]

I got your message Murf. If it is opening and closing with humidity that must be a very wet and then very dry environment? I would wait until it opens and then glue and clamp but with that curve you will not get good clamping.

I get the grinding it out but that will remove the veneer also and then the gap is permanent and no amount of clamping will close it. Are you going to put in a new sliver of veneer?

The curve cracking is a hard fix and very few people can do it successfully.

I would tape the inside cabinet where the crack goes through. Then fill it with wet glue and let it dry. If the veneer is lifted don't glue it down until the wet glue is dry and the crack is now stable.

Then inject undiluted glue under the veneer and preferably use a hand made inside curved piece of pine to the same curve and use strap clamps to hold it down. Use a piece of wood across the back of the cabinet so there is no way for the cabinet to cave in on itself. Then when it is dry you can use color sticks or tinted wood filler to fill any imperfections. Some people even paint the grains in to match it.

Aside from that it is a full veneer strip and replace  

Kirk