Muskies will be fine in cold water. Tigers (musky x pike hybrids) are very hardy. Pike do well in the far, far North. Think Alaska and northern Saskatchewan. Don't grow fast but do well and get big given the time. Tigers generally won't reproduce so the population is very controllable. Neither muskies or (especially) pike are known as "warm water" fish. Big pike in particular prefer cool water most of the time. Muskies like it slightly warmer.
Enjoy your new "residents" and expect to lose a few rigs to the toothies