First time slow cooking and its a leg of lamb!

Going in at the deep end!

Trying to work out the timings / best approach for this beast. The whole leg of lamb (Welsh of course) is 2.48 kg so pretty big. My plan is to brine it for 12 hours and then I was going to follow this recipe – https://www.goodhousekeeping.com/uk/food/recipes/a574748/slow-cooker-lamb/ but increase the ingredients by x1.5 due to the size.

I am using a Ninja Foodi Possible 8-in-1 Slow Cooker if that makes any difference (first time).

I also think I should brown the lamb afterwards to give it a crust.

So the mistake I think was planning to eat at 1PM – as I need to work backwards – 15 min resting, 15 min browning, 30 min resting, 7 hours? cooking on low?, 12 hours brining, which means start brining 5PM day before and start cooking 5AM – what do people think? Is 7 hours enough time considering the size?

Is it best to use a meat thermometer to confirm or start it an hour earlier at 4AM and just check if it falls off after 7 hours and just keep warm in the slow cooker.