Structurally, it doesn't look too bad given that it is not in the direct path of the exhaust, ie, the wind loads would not be so bad. Any such wind loads would also be applied at the base of the structure so the moment would not be so large. A decent hurricane would be worse, I expect.On the last pic, are they sure the lightning rod tower standing right in the fire pit is OK?
Thermally, the loads would be very transient and hence not a big issue. Consider what some elements of the LC-39 Fixed Service Structures are exposed to during a Shuttle launch.
I notice at Baikonur the towers are further away. Maybe the greater lightning risk (due to tropical location) requires such proximity?