Hanging a Tree Swing

My biggest concern is that silver maples are notorious for having weak crotches that grow at angles, rather than perpendicular to the main trunk; however, I can also find articles that argue these trees get bad reputations based on hearsay more than fact.

If you can't show that it's ok, then I suggest not risking it.

You could still attach as you suggest AND mitigate your concern by bracing your connection point back to the vertical truck, this allows for the angled branch to LOCATE the swing, and the main truck to take the FORCE (of concern, the branch only experiences compression force and it is very strong against that)

I would not use any type of bolt through the branch.

i would use a rope or, better, a strap to make a collar around that branch and another around a branch behind to share the load, which will give ample support. Think of those 2 or 3" wide loading straps and then use a D-link to attach the swing to the strap, that way you won't damage the tree.

You could esily brace to two other branches...

Silver maple wood is not strong and crotches make it worse . From Handbook of Physics (1936 ed. - I don't think this is on line.) .Silver Maple= 6.34, Sugar maple =10.97, White Oak = 10.95, Loblolly Pine ( typical southern pine) =9.09 ( units Kg/mm square). Also , dynamic loads like a swing ,produce higher stresses than static loads such as a weight. If the tree had a single trunk up to about 20 feet ,it would likely be strong enough. Maybe just make maple syrup if you as far north as Chicago ( too late for this year).

Tree farmer here. Other comments about the weakness of silver maple are right on. This one has very narrow crotch angles. Not recommended.

Look: here I can get a used 35 foot telephone pole for $28. Buy two. The two butt ends and some 2 7/8 gas pipeline are the support for the swings. The two top ends are set to form a triangle with one of the swing supports, and you can do some assortment of climbing bars.