main problem with these bearings is crystallization within the metallurgical structure which only shows up under certain load conditions, and is unrelated to dimensional tolerances of the finished product.
Manganese inclusions, I used to buy Steel for major Shell bearing manufacture where the same problem results in a different issue when the shell half circle is formed. You can specify an acceptable level of Manganese Inclusions, get all the certificates under the sun saying the blast melt was tested and the low level required for bearings was found. But in the end its a single sample from a 25T melt that goes into the slabs that are then rolled. Your sample may be good but its a crapshoot if the slab your bearings end up coming from have a bad 30kg section with a high inclusion level you are stuffed. Only way to reduce the problem was to select a specific steel mill you trusted and insisted on only using them and audited their tests annually to see the average levels were low.
I bought 30K Tonnes of bearing steel a year and could not get it 100% even being able to say only use that mill, what chance has a small low volume outfit got buying from a stockist and insisting it must come from a specific Belgium Mill.