I'd not expect any specific problems, except the usual - if a tank mate might fit into the vaillantii's mouth, it is a risk. Of course, the old wisdom that every tank differs and our hobby is a gamble always applies too.
I have had the three mentioned fish kinds in a 4500 gal for a few years but along with many other tank mates.
If my vaillantii experience is of any guidance, you may have many years before it reaches 2', if ever. Mine came from Wes (Suriname) and has been 18"-20" seems for the last 2+ years, not showing any signs of growing while feeding with vigor.
Are you getting Numbnuts' fish? If so, it'd be cool for us to continue learning about this specimen.