Contact USCIS directly to inquire further.

Refer to the N400 processing times for guidance.

You may apply for citizenship and provide explanation for extended absence.

Your wife’s GC application will not be approved.

Please rephrase your question for clarity.

You may reapply for your wife as spouse of USC.

Yes, you may travel while your N400 is pending.

Yes, your mother may apply for a visitor visa.

Likely 4-8 months but no specific window is available.

Best to discuss the situation with an attorney to discuss next best steps.