I have very simple views on this and once we talked it all through, DH has been supportive. The kids (from 2-18, DSCs and DD) don't have to like what is served. They don't even have to eat what is served. But there is ONE meal and that is it. Period, end of. If they don't want to eat the meal on the menu, they can make toast or tinned soup. There is no second meal prepared for them, and they aren't to go and fix their own alternate meal either - we can't afford that, we don't want to clean up after it, and its not a precedent we want to set.
We do try to be considerate of strongly held tastes. So for instance we hardly ever (but not never!) have mushrooms even though I love them! But we don't pander anymore.
Your DSCs are going into high school. They should be helping with meals anyway!! They can certainly do simple things like warming up leftovers or making a simple pasta meal. Maybe get them to make up a week's menu with you each week (or in advance of their next stay), and assign them each a meal of their choice to prepare. You might need to do it together at first. On "their" meals, they get more choice; on "your" meals, you choose.
In our house, the teenagers each cook three times out of every fortnigsht - one weekend evening and two weekdays. They are free to make whatever they want to cook on their nights (within reason - can't be too expensive and must be moderately healthy, and it needs to be sorted out at the start of the week when we do the shopping). Usually though they just stick to the same handful of dishes.
DSD is competent in the kitchen, likes to cook, and will make meals like bolognese from scratch, or bangers and mash.
My DSS - 15 - is pretty useless at meal preparation; on his days we tend to have ready meals. But he can steam vegetables, and his 'signature dish' is a prawn stir-fry. I don't especially like it - not a fan of sprouts - but it is 'his' turn.
sc here 50/50, very limited eating habits. will suddenly go off things that used to like. met with mum says i dont like this ect. both going into high school soon and still eat like young children. frozen stuff, bits of veg, certain meats but no meals if that makes sense wont eat casseroles,wraps,bologneses. we are ending up doing 3 different meals and its so wearing. we cant really afford to keep making different meals for everyone. meals obviously not dfilling them up as no soon as down from table going to get crisps/yoghurt but taking literal hours over tea. part of me thinks my house, eat what is made for you but then every night becomes a battle. wwyd??