Modifying scratch location and coredumps has become increasing finicky via PowerCLI and Vcetners WebGUI. I find that making these modifications on the host directly provides the least headache inducing response currently.
First Off Scratch Location:
vim-cmd hostsvc/advopt/update ScratchConfig.ConfiguredScratchLocation string /vmfs/volumes/<DATASTORE>/.locker
And CoreDump Location
esxcli system coredump file set --unconfigure
esxcli system coredump file add -d <DATASTORE> -f ESX.dump --enable=true
esxcli system coredump file list