For anyone else who has this problem I found a nasty solution. I wrote a webscript to unlock the node in the REST api's error message. Then I ran and got ANOTHER locked node..and then another… I had to do this 8-10 iterations, but finally the curl command succeeded.
Webscript was:
var foundNode = search.findNode("workspace://SpacesStore/9b0c6637-6b04-4454-be8b-a3963262a658");
foundNode.unlock();
foundNode.save();
Moving on but…ughh…this doesn't give me confidence in the product!