From Vanguards website: Looks like the short answer could be yes.
"Eligibility is based on total household assets held at Vanguard, with a minimum of $50,000 to qualify for Vanguard Voyager Services®, $500,000 for Vanguard Voyager Select Services®, $1 million for Vanguard Flagship Services®, and $10 million for Vanguard Flagship Select Services™. We determine eligibility by aggregating assets of all qualifying accounts held by the investor and his or her immediate family members who reside at the same address, including investments in Vanguard mutual funds, Vanguard ETFs®, certain annuities through Vanguard, The Vanguard 529 Plan, and certain small-business accounts. Assets in employer-sponsored retirement plans for which Vanguard provides recordkeeping services may be included in determining eligibility if the investor also has a personal account holding Vanguard mutual funds. Vanguard ETFs and Vanguard mutual funds held in a Vanguard Brokerage Account are also included when determining a household's eligibility; other assets held in a brokerage account are not.
Qualification criteria (for example, asset levels) for Flagship and Voyager Services are subject to periodic review by Vanguard and may change at any time. Vanguard reserves the right to discontinue enrollment in any of these services or reassign any investor, without prior notification, to the appropriate service level if the investor fails to continue to meet the applicable qualification criteria. Vanguard reserves the right to amend or cancel selected features and benefits at any time without prior notification.
In addition, ongoing access by any particular investor to individual services, discounts, and exemptions is subject to periodic review and may be restricted based upon criteria established solely by Vanguard. While Vanguard Flagship and Voyager Services are complimentary, some underlying services may charge fees and expenses. Vanguard does not guarantee any level of service."