Flight questions

tldr: Can I book two separate one-way flights for either end of a cruise?

I’d initially planned to do our flights through Viking as part of the cruise package, but they are charging over $250 per person to 1) actually talk to the person booking the flights and 2) come to the ship on our own steam. We did a pre-cruise extension last time and did not enjoy the airport bus experience. Plus, we can manage a taxi/hotel ourselves for waaaay cheaper. I’m thinking we’ll get a refund the flight portion we’ve paid and then book flights/hotels/taxis on our own. Is it a problem if I book 2 different one-way flights on different airlines?