Hey.
I kept a 34 gallon solana for over a year with a Dwarf Zebra Lionfish, 6-line Wrasse, 2 False Percs and a Coral Beauty....NO issues. He didn't even come close to trying to get any of them, and none of them were full grown (all less than 1 year). Just keep them well fed!
Hope this helps.
I would be very nervous mixing the two. I once had a fu man chu lion and he ate a sixline wrasse the same size he was. Clownfish would make an easy target.
You would be surprised at how large they can open their mouths. I didn't see it happen but the lion had a large buldge in his stomach and the six line was no where to be seen.
I would put the probability at more like 60% that eventually the lion will have Clown du juor. Unless the clown is a maroon or tomato.
Give him a tank with larger tankmates.