Issuing that command in a terminal after starting the menu editor resulted in no output at all, just a new prompt, so RMB-ME is not using alacarte. I started Menu-Administration-System Monitor and it shows an interesting Process called cinnamon-menu-e - maybe this represents another fork from alacarte ? And if I close the menu editor, cinnamon-menu-e disappears from the list of processes.
cinnamon-menu-editor is NOT in the list of packages displayed by Synaptic Package Manager on my system, either installed or available to install. If I search on cinnamon-menu-e there is no such package, the only package selected is one called nemo-fileroller. BTW, the only package that shows as installed when I do a search on 'menu editor' is alacarte.
I don't really have 2 ways to invoke the menu editor since the 2 options are using different data/control files as shown by the menu contents. See above. The only menu editor that actually changes the Menu in use is RMB-ME aka cinnamon-menu-e
I'm beginning to think I may have installed alacarte myself and thereby shot myself in the foot when (soon after I installed LMDE) I was trying to work out how to edit the Menu. Unfortunately although I've always advised people I've tried to help over the years (*) that they must document all they do, I don't always take my own advice
(*) that is with Windows etc, not with Linux in any shape or form