How do I heat my borosilicate reflux column?
That should pose no issue regarding the glass

Without images to see how unevenly you will apply the heat, I have to modify my instinctual reaction "That cannot possibly be an issue" to "Most likely it will be OK". I'd be much more worried about variation in the distilling if you are at some point drawing a distillate. If you cannot control the heat flux, the yield and temperature profile will be offset from the theoretical and can (if the process is delicate) lead to variation in the results.

But borosilicate glass is sturdy, you can probably heat it with a naked propane flame - it is designed to have a low thermal expansion coefficient. Directly from that, it will have a high thermal shock resistance.