I haven’t cooked much with runner beans after moving to the US because I rarely find them. Seems like there are different varieties, but the ones I’m familiar with look like this: https://www.greedygourmet.com/recipes-by-course/side-dish/runner-bean-puree/ We harvest them when the peas are still tiny and soft, so the pods have a good texture.
We usually braise runner beans, often with some pork (my mom likes to use leftover pork stews, with a bit meat and the sauce) and potato. The beans will soak up the sauce and taste great.
The other method is called “焖”, or steam fry, which I think will work with this recipe. You can blister the beans, but maybe not wait until them to cook through. Once their surface is a bit wrinkled, you can proceed to add the sauce etc. Then you can cover the pan, so the runner beans will be slightly steamed through and become tender. The result is less crispy beans, but the texture will be tender and the beans will soak up the sauce.