Well, with most installers you could insist but it doesn't mean they will do it.
You could cut it short where he can't use it, but it doesn't mean he will do a good job running new stuff.
Cable age isn't so much of an issue vs cable type.
However, I have seen MRV run fine on RG59.
I suppose the best question for you would be if you had to pay for it, would you have it done?
If so, offer the installer some money to run new lines and see what he says.
If not, then I would just see what the installer does.
just my $.02