My first restaurant job was in a NY Times 4* French fish restaurant. One of the menu items was "grilled salmon." But there was no grill in the kitchen. So as oldschool suggests, we marked the fillets in cast-iron grill pans, chilled them down, and then finished them to order in the oven.
I would not par-cook a sauteed fish fillet -- that seems to me an invitation to overcooking. But yes, you can sear the fillet fast and then finish it in the oven the same way. I've done that everywhere I worked saute station.
The bigger question is: can the kitchen be set up to accommodate the menu, or can the menu be changed to take the limitations of the kitchen into consideration? Quality can suffer from too many work-arounds.