You have found three groups that sound reasonable, and Dad has said he will think about it. Most of the difference between them is not in the name on the flyer. It is in who leads the room, who comes, and what the first night asks of a man who has not talked much since the funeral. Compare them on those points.
Local option: New Plan Care gives families in the St. Louis area in-home help so a parent can stay home: companionship, help with bathing and dressing, meals, and overnight care. Call (314) 405-0887.
What to do tonight
Write down three things. First, whether he wants a group of men, a mixed group, or one-to-one support. Second, how far he will travel and whether you can drive him. Third, whether he can sit in a room and listen without being asked to speak. Those three answers will rule out more groups than anything else.
Questions to ask the group
Ask who leads the group and what training they have in bereavement. Ask whether the group is open, so people can join any week, or closed, so the same people meet for a set run. Ask whether it is for people whose spouse died recently or for anyone at any stage.
Ask how many people usually attend, whether he can come once and leave without any commitment, and what happens if someone misses several weeks. Ask whether there is a waiting list, a screening call, or a form to fill out first.
Ask about cost in plain terms: whether there is a fee, whether it is covered by his insurance, and whether it is free through a hospital or hospice program. Ask it directly, because groups vary here.
If your family had hospice care, ask whether that program offers bereavement support to family members after a death. Some do, and asking commits you to nothing.
What to compare between two groups
A group that meets in the same room with the same facilitator each week usually builds more trust than one that changes leaders often. A group run by a hospital, hospice, or established counseling program often has a clear way to refer people and a way to reach the facilitator if something comes up. A parish or community center group may suit him better if he already goes there for other things.
Compare the first-visit experience as well. Does someone greet him at the door, explain how the evening runs, and say that he can listen without talking? Or is he expected to introduce himself and share on the first night? The answer tells you how the group treats people who are not ready.
Signs a group is not right
Be wary of a group that pushes people to share on the first visit, promises that grief will end by a certain point, sells products or courses during the meeting, has no named facilitator, or cannot tell you clearly what it costs.
When to call his doctor now
If he has not been eating or sleeping for weeks, has stopped doing things he used to do, or has pulled away from everyone, call his doctor and ask for an appointment soon. If he ever says he would rather not be alive, do not wait for a group to start. Call his doctor the same day, or call or text 988, the Suicide and Crisis Lifeline, right away.
Local places to start
For St. Louis options, the local help page for a widowed father in St. Louis lists places to begin. Use the same three-point list from tonight with each one.
You do not need the perfect group. You need one he can walk into without being pushed, and you can check that with one phone call.