I am looking at this improved spec. sheet. It has some useful PCB layout tips for EMI suppression.
https://www.ti.com/lit/ds/symlink/tl494.pdf
DTC soft start seems simple to add at 180Khz as it only requires a 0.1uF cap/ 2.7K combo for 50 cycles start.
I have noticed that most TL494 sample circuits driving a PNP switch include a pullup base resistor at about 1/3rd the value of the base drive resistor. Have a look at figure 15. They mention discharging carriers for proper switching. Does this mean that the transistor is hovering a long time in linear mode without that kind of pullup?