When to pay Medicare Part B penalties and when to stay put with existing plan?

Hi all -

I'm in the process of sorting out the best path forward for an 81 year old who left employment in 1993 (when he was 55) and never enrolled in Medicare Part B. I have an appointment next week with the regional SHIP which offers free counseling. And Realyreal per your advice I am also looking for a Medicare specialist to weigh in. But hoping to tap into this Forum knowledge as I continue my research.

This investigation was inspired by the elder's recent move to assisted living and the offer of a Medicare Advantage On-site Special Needs plan that requires enrollment in Parts A and B (that was an Anthem plan that I posted about last week). While he is not currently eligible for that it is very attractive idea as more of his health care would come to him vs. him needing to manage outside appointments and transportation (even with the limited help of the AL that is hard). He has underutilized his insurance in the past and didn't see his doctors regularly, to the detriment of his health. He's been hospitalized with extensive time in SNFs twice in the last two years. He currently has a Blue Cross PPO through his retiree group plan which I was told means he cannot demonstrate "creditable coverage" and so would pay at least a 160% penalty if he enrolls in Part B (the staff at the group plan told me that medicare only honors employer group health plan coverage, not retiree plans, in calculating penalty payments). However the retiree group reimburses for the base cost of Part B, so all he would pay is the penalty portion. And they also offer a plan he could switch to that is like the Anthem one: SCAN Health Plan with very low or no co-pays and full coverage of many items that he currently pays at least 20% of, plus extra assistance with transportation and care coordination.

I requested and received 5 years of his claims and payments through his current provider and I'm analyzing that now. Also confirmed that the only pre-existing condition that would impact coverage if he switched is end-stage kidney disease which he doesn't have, and that he isn't near his lifetime max coverage in the current plan. He isn't attached to any of his old doctors since he hadn't been going to them at all! Based on my initial calculations, his monthly premium would actually go down by $11/month, even with the penalties, and that doesn't capture the savings in out of pocket expense.

So have any of you faced a similar decision about enrolling very late in Part B? How did you make your decision? What am I missing here that I should consider?

He has taken to this AL like a fish to water - LOVES it and the people are wonderful for him. So he could have many happy and healthier years ahead. Changing plans could help get him better access to care at a lower overall cost, even if it means paying that penalty. Thanks for any experiences you can share!