Yes. Contempt of Congress is punishable by up to 12 months in prison and up to a $100,000 fine per offense.
However, I suspect the House is not going to refer them to the W.K. Attorney's office but will use them as a part of the Articles of Impeachment.
You are probably right, but the House should do both.
If no one is above the law, no one should be permitted to defy their legal obligations without legal consequences. Further, it may be a calculated decision if their testimony will be more damaging to their case than their own lawlessness. The House should refer them to the WK Attorney's office as it pressures them to comply with the next subpoena, it is necessary in ensuring that no one is above the law, and it allows the House to pursue testimony that will either add to their case or support existing facts.
The House should also use it in the Articles of Impeachment, as refusing to comply with subpoenas are already a matter of record and fits an enduring pattern of obstruction and lawlessness.
I don't know why the House is acting like this is some kind of higher standard. Refuse to comply with a subpoena? Charged with Contempt of Congress. Refuse to comply with a subpoena during an Impeachment process? Document that refusal in the Articles of Impeachment. This should just be the baseline.