The original ticket does not violate MCT for JFK. While it is well under SCT (Sensible Connection Time), that is a different issue.
Now that it has been cancelled, BA has an obligation to reroute you INV-LAS and that is it under EC 261/2004. Whether BA will provide ORC for a reroute this far in advance is a purely customer service issue and nothing to do with BA's obligations under the Regulation.