My husband is military and is not filing in Virginia. is his income part of VAGI?

No.

If your spouse is not a Virginia resident and you are, you must file a separate VA tax return. This will only include your income as Virginia AGI. You will need to prepare a full separate Federal and state return for the one tax needs to file a VA resident tax return.

See the following from Virginia - Military Tax Tips:

If you are a resident and your spouse is a nonresident (or vice versa), you and your spouse must file separate returns. Income, dependent exemptions, and itemized deductions must be allocated under federal rules for separate filing, as if you had filed separate federal returns. As a general rule, the spouse claiming an exemption for a dependent must be reporting at least half of the total federal adjusted gross income. In addition, the spouse must be able to support his/her claim of itemized deductions. If it is not possible to account for the deductions separately, the deductions may be allocated based on each spouse's share of the federal adjusted gross income. When filing a separate return, the other spouse's income, exemptions, and deductions should not be included.