It really depends on what time of yerar we are going. We had the same situation as you the last trip. We were there spring break - the week before Easter. The day we visited they closed the park to new admissions at noon - it was so packed. Anyway we got to AK at 9:05 and rushed back to the safari. The line was huge - we didn't get off the safari until 10:20, we then rushed to breakfast, arriving at 10:40 (10 minutes late). They took us without problem, but we were seated in an overflow area - out on the porch rather than the main dining room. That was the beginning of a rather disappointing day at the park. Just too crowded, too long of lines to enjoy much of anything.
If you are traveling at an off time you should have no problems doing the safari before breakfast. Just arrive at AK at or before opening and allow 25 minutes to walk from safari to breakfast - they are at opposite ends of the park.
ps - your experience may differ but we did not like the 10:30 seating. Food was taken away and missing from the buffet. They consoldiated two buffet tables into one, and generally rushed us to get done so they could set up and start serving lunch.
Hope you have better luck.