Nighthawk M2 - Best Extender?

Hi Folks, technology-challenged DIYer here....

Living in rural SA we get either fixed wireless (useless) or 4G(marginally better).

We have a data SIM so have gone with an M2 using our Telstra data allowance (80G). I have an antenna to put up soon, to connect into the M2, but in the meantime need to set up an extender as it is a big old stone house and range is poor. Local electronics place sold us a couple of extenders; Tried a TP_link wifi device - useless. Tried a TP-Link Powerline device - useless

Will the Nighthawk X6 EX7700 extender work with the M2 device (compatible signal, speeds, technology etc)?

Need something with enough grunt to work across a large home with thick stone walls, and across multiple rooms.

Any help is appreciated. Cheers