The cache is not at the listed coordinates.
Imagine there's no seven.
It's easy if you try.
The real coordinates are N 61 45.4124 W 154 13.6304 in a world with no sevens (eights or nines), but our world has sevens (eights and nines). So adjust accordingly.
You, you may say I'm a dreamer.
But I'm not the only one.