Hmmm...... I would expect kinda serious mess on this route (I don't want to say it's outright impossible, but quite a problems are to be expected) First, I doubt that it is possible to make free bromanhydride of N,N-dimehylglycine (without a salt on amine part). Second, indole acylation in 3 position is not exactly simplest thing on earth (indole can as well and preferably acylate on N; that standart dmt route via oxalylchloride is exception rather than rule, which is possible because oxalylchloride is not a typical chloranhydride)
Well, I can be wrong, I confess, that I'm a bit rusty in finesses of indole chemistry. Maybe some clever guys already discovered reliable ways of indole acylation (perhaps with nontraditional Lewis acid catalysis) and I just don't know them?
My personal half educated opinions only.
Greensnake