Learn Finnish: Tämä hiihtokeskus saattaa sopia lasketteluun. - This ski resort might be suitable for downhill skiing.

You are right that saattaa can mean 'to escort' or 'to bring about'. However, it also functions as an epistemic modal verb expressing possibility, meaning 'might' or 'may'. When used this way, it is always followed by the first infinitive, which is sopia in this sentence.

Why is laskettelu in the illative case (lasketteluun)?

The verb sopia (to suit, to fit, to be suitable) governs the illative case when you are stating what something is suitable for. Therefore, 'suitable for downhill skiing' is expressed as sopia lasketteluun.

Could I use the allative case (laskettelulle) with sopia instead?

Not usually for an activity. When sopia means 'to be suitable for a purpose or activity', it takes the illative case. The allative case (ending in -lle) is mainly used when something suits a person, such as Tämä sopii minulle (This suits me).

Is there a difference in meaning between hiihto in hiihtokeskus and laskettelu?

Yes! Hiihto refers to cross-country skiing, while laskettelu specifically means downhill or alpine skiing. Interestingly, a hiihtokeskus (literally 'cross-country skiing center') is the standard word for any ski resort, regardless of the type of skiing. This sentence is specifically highlighting that the resort is good for the downhill variety.