Yep your right, its a non-starter even if they were the only occupants. Albino rainbow sharks are very territorial so not the best of mates for male betta. Albino RS also require a much bigger tank than 10 gals. If you are refering to the 10gal in your siggie, you really dont wanna be adding anything anyway, as its pretty over-stocked.
If your referring to the tank in your sig, i wouldnt put anything else in. The rainbow shark is also highly territorial and i have found nippy,and will get far too big for a 10 gallon tank.
I wouldnt put a betta with any of the fish listed in your sig to be honest.