They are most likely "Kailh Choc V2". They are clones of "Cherry MX Low Profile" on the outside but not interchangeable due to a different pinout.
Some tech news sites have claimed that Kailh makes these.
Kailh manufactures also the "Logitech GL" (Kailh Choc) and "Logitech GX" (Kailh's Cherry MX-clone).
Cherry MXLP is not available in other than linear, and TTC's proper clone is not available in tactile.
While they have made their own switches in the past, these look exactly like premade switches. I don't feel that the model numbers serve to help identify the actual switch.
'MX' made me think it might have been Cherry, but the review says Chocs, so that's what I'll believe. MX is probably included to signal 'MX compatible stem'.
i think Logitech started with Cherry switches in their early mechanical keyboards and later they switched to their own switches, some are based on Cherry MXs and some are not..
From the name and some images my guess is that this ones are based on or at least compatible with the Cherry MX\MX Low profile switches..
But Logitech has the (bad) habit of mixing different models of switches in the same keyboard model.. I have two G512 here..
The first one, a tactile silent, use Romer-G switches, those are made by Logitech itself, not sure if anyone else use those.. they have their own Keycaps, not compatible with anything else AFAIK..
The other one, a tactile clicky, it uses GX Blue switches (their version of the Cherry MX Blue) that is compatbile with Cheery MX keycaps..
My guess would be that those Graphite MX are likely like their previous GX switches.. based on Cherry but manufactured by Logitech or some by some contractor on their behalf.. not much information out there about those yet..
But, they should be vaguely similar in feel. If you're looking for something clicky, the Kailh low-pro switches may be a better choice, since they developed their clickbar for the 'tactile event'. IMO, the clickbar switches are better than click jacket/etc for clicky switches.
Either way, you could order some loose switches as a sample before committing to one or the other. I'd not bother with the tactile (non-clicky) one, but that's just my own opinion.