What is better for chilled cheesecake - pectin or gelatin?
Probably the jelly is something like the brand Oetker which comes clear or fruit-flavoured. It is indeed poured warm; cheesecake will survive if it's a cm or less layer.

Alternatively, boil up some apricot jam (or strawberry), take off heat a few minutes and sieve through a tea strainer over cheesecake. 
Keep stirring the pot if you are slow.