I hope this message finds you well, present circumstances excluded. I am a licensed attorney with over a decade litigation
I will answer your questions in the order in which they appear:
1. Filing a motion to quash as you sit here today will likely only serve to temporarily delay the issuance and the execution of the subpoena, as you sit here today. For the motion to have any real affect, you are going to need to first file a motion relative to the default judgment to re-open that case. Once that happens, you can then file a motion to quash which should be able to at least stay the proceedings until your challenge to the default judgment can be heard and ruled upon.
2. If you go ahead and file a challenge to the default judgment (which could be in the form of a Motion to Set Aside), you can submit a certified copy of that motion to the bank and instruct them not to answer the subpoena until you Motion has been ruled upon and a certified order has been received by them.
In short, the whole methodology surrounding this issue depends on you immediately filing a Motion to Set Aside relative to the default judgment order. Once that is done, you have more legal maneuverability.
You need to understand though that a motion to set aside a judgment that old rarely prevails. However, that is your only legal option at the moment.
Let me know if you have any other questions or comments.
Best wishes going forward!