Sorry, would be happy to help, but don’t know much about that car. Can say the 9.6V (8 cells) is not common, most 1/10 scale hobby stuff starts at 7.2V (6 cells). Might be an issue with battery pack size, in addition to connectors.

Good part is you’re asking a very good question ahead of time. RC does use a variety of connectors, something to be aware of when purchasing. Learning to solder connectors of choice is a common thing.

Correct on the mAh rating being an indication of relative run time.

Oh, welcome to the hobby and forum.