Please see the FAQ. The methods you give involve joining the bulb to the network again. That’s actually not necessary most of the time.
Instead, you can simply prod the bulbs to look for the Cordinator they already know, without having to do any “add a device” step on the SmartThings side.
SmartThings staff that have posted that the reason that the GE bulbs are not listed as being officially compatible is that they have a firmware problem that causes them to not know what network they belong to when they wake up after a power outage. The information is still stored in the bulb, but for some reason they’re not using it. Apparently GE has said they may update this firmware in a few months, but who knows when. Meanwhile it’s the reason why this is the brand that has this problem more than any other.
You just have to get the bulb to use the information that it already has. That process is almost always easier than doing something through the SmartThings add a device protocol.
But again, see the FAQ.