I haven't run across your situation, but I believe military couples (both active) can file with different status for federal, and state in any state.This is what turbo tax says  about OK " You can also file married joint for federal and separate for CA and OK." this was an answer to a military couple one with a record of resident in CA and one in OK

This is from page 9 of 2025 911.It is different from what you are saying????

The filing status for Oklahoma purposes is the same as on the federal income tax return, with one exception. This
exception applies to married taxpayers who file a joint federal return where one spouse is an Oklahoma resident (either
civilian or military), and the other is a nonresident civilian (non-military). In this case the taxpayer must either:
• File as Oklahoma married filing separate. The Oklahoma resident, filing a joint federal return with a nonresident
civilian spouse, may file an Oklahoma return as married filing separate. The resident will file on Form 511 using
the married filing separate rates and reporting only their income and deductions. If the nonresident civilian has an
Oklahoma filing requirement, they will file on Form 511-NR using married filing separate rates and reporting only
their income and deductions. Form 574 Resident Nonresident Allocation must be filed with the return(s). You can
obtain this form from our website at tax.ok.gov.