Your lawyer is right. Please see the lines below from page 15 of the i-485 instructions (
https://www.uscis.gov/sites/default/...85instr-pc.pdf).
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You are NOT required to submit Form I-693 at the time you file your adjustment application, but may do so if youwish. Because of the time-limited validity of Form I-693, you may choose to submit your Form I-693 after you file your Form I-485. You may also submit Form I-693 in person at an interview in a USCIS field office, if an interview is required. By waiting to submit Form I-693, you may avoid having to repeat the immigration medical examination.
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