"After TCJA they have until the extended due date to do so, I’m just wondering mechanically how it should be input into the return."

What was the reason that they got reported as a loan offset? Did they lose that job or violate the repayment terms? Has it been 5 years since they took out the loan? Does the new employer accept offset rollovers?

https://www.irs.gov/retirement-plans/retirement-plans-faqs-regarding-loans

"a plan loan offset amount is treated as an actual distribution for rollover purposes and may be eligible for rollover. If eligible, the offset amount can be rolled over to an eligible retirement plan. Effective January 1, 2018, if the plan loan offset is due to plan termination or severance from employment, instead of the usual 60-day rollover period, you have until the due date, including extensions, for filing the Federal income tax return for the taxable year in which the offset occurs."

You asked about IRA:

"2. Can I roll over the outstanding loan balance from my retirement plan into an IRA?

IRAs (including SEP-IRAs) do not permit loans. If this transaction was attempted, the the IRA could be disqualified."

The most recent changes are from CARES Act. For termination repayment, what they have is the time given by the original plan administrator, which can have been longer than in the past.

https://www.irs.gov/newsroom/coronavirus-related-relief-for-retirement-plans-and-iras-questions-and-...

"Certain loan repayments may be delayed for one year: If a loan is outstanding on or after March 27, 2020, and any repayment on the loan is due from March 27, 2020, to December 31, 2020, that due date may be delayed under the plan for up to one year."

"It is optional for employers to adopt the distribution and loan rules of section 2202 of the CARES Act. An employer is permitted to choose whether, and to what extent, to amend its plan to provide for coronavirus-related distributions and/or loans that satisfy the provisions of section 2202 of the CARES Act. Thus, for example, an employer may choose to provide for coronavirus-related distributions but choose not to change its plan loan provisions or loan repayment schedules."

Only you know what applies, here. For the year 2022, you are entering what happened, not what they intend to do.