I’ve been having issues with my WiMo Bulbs ever since I first set up my smartthings hub & ditched my WiMo Link…
Specifically some bulbs will stop responding temporarily but be fixed several hours later.
In one specific case a bulb in one specific 3 bulb array will stop responding all together. They are literally a few inches apart but one spot will always cease to function regardless of which bulb I use…
Can smartthings work through WeMo link as it seemed more reliable than ST by itself…
I have had 4 Wemo LEDs since about the time they first came out. Despite the (same) problems as you describe, the link alternative to me was always much worst. Of the 4 connected to ST, two act up on occasion. Only way to get them back is a complete reset. Wish I could trade them for Philips Hue 
But alas, I digress…
No, the Wemo Link does not work along with the ST hub.
I was having major problems with my WeMo devices and I have a number. I found if I used my second router to extend my WiFi network I would have problems. Even with them being on the same network name etc. So I used a WiFi finder app and found the WeMo devices on the second router were the ones that gave me problems. I have a pretty strong WiFi signal with my Airport Extreme Base Station but wanted to extend my Wifi. So I removed the second router and repowered the devices that didn’t connect and my problems went away, once the devices were again on the single router. This is something that shouldn’t happen if you are on the same network, but for only WeMo it did. Since I am now on the one router not a problem in many months. I am not sure if this is your problem, but I thought I would put it out there.
I ended up using iFTTT to share the bulbs via WeMo link, but noticed something which has me perplexed…
Last night I noticed the same pattern that ST was giving me… Ironically enough I had plunged in my WeMo Link right next to my ST hub.
When I relocated the WeMo link the bulbs worked just fine. Seeing that the problem bulb location is in a metal cup that points directly away from the ST bridge (and where my WeMo link was plugged in) is making me think that perhaps the issue is that the signal is being blocked due to the orientation of the bulb cup…
That being said, this still doesn’t explain the issues with one bulb that is fully out in the open about 15’ from my ST hub with nothing between them…
Oh, and I do have a multi hub network, 2 airport extreme base stations, but this can’t be playing a role in the issue… The bulbs don’t use WiFi, they connect directly to either the SmartThings hub or WiMo link, so network wouldn’t impact bulbs individually. Seeing as some bulbs work fine while other are problematic, it limits the issue to between the bulb and the link device…
I also have 20+ other WeMo type devices (switches/outlets/insights) all of which have virtually no issues on my multi-hub network. My 2nd hub was setup as a bridge, so all items remain within the same network regardless of what hub they end up on…