I don't believe I have seen this reaction scheme discussed on here before, but it seems like an easy route to TMA-2 using an easily accessible precursor.
Search for "2-methoxyhydroquinone" gave one article posted by Rhodium that follows a similar route, however the hydroquinone rather than an aldehyde is dimethylated and it is never formylated.
a. Dakin reaction on vanillin yields 2-methoxyhydroquinone. I believe H2O2 under alkaline conditions will accomplish this.
b. Your choice of a phenolic ortho-formylation on 2-methoxyhydroquinone yields 2,5-dihydroxy-4-methoxybenzaldehyde.
c. Dimethylation w/DMS yields Asaronaldehyde [2,4,5-trimethoxybenzaldehyde]; plenty of representative procedures of this on rhodium.ws.
I shouldn't have to explain how to get to the target compound from there. Anyone see any potential problems here?