Organic conversion involving Grignard reagent and alkyl group with a carbonyl carbon on an benzene ring

I have been asked to synthesize the organic compound shown below using the following reagents and solvents.


$\ce{Mg, Zn, Hg, FeBr3, AlCl3, Br2, LiAlH4, KMnO4}$, dil. $\ce{H2SO4}$, conc. $\ce{NH3}$, conc. $\ce{HCl, H2O, D2O}$, ether, ethanol, $\ce{CH3C(O)Cl, CH3C(O)CH3, C6H6}$.


I have done it as shown below.
[![conversion](https://i.stack.imgur.com/rylUV.jpg)](https://i.stack.imgur.com/rylUV.jpg)


But in the answer given that the -$\ce{C(O)CH3}$ group attached to the benzene ring is reduced to -$\ce{CH2CH3}$ before introducing $\ce{Mg}$/dry ether.
Then the $\ce{Mg}$/dry ether is introduced followed by $\ce{D2O}$. Then the alkyl group is oxidized and so on...


Is there is specific reason for doing that or is my method correct?


