given that no one really read [or reads] the pbp manual and the declining interest in 8 bit mcu's and pbp in general
I hope your endeavours are not wasted.

try this for ioc
dt-ints is not a panacea for pic interrupts some understanding of the hardware is essential for meaningful results, not all 8 bit pic mcu chips are equal its possible microchip may have implemented module hardware in various different ways so always check the datasheet. ioc interupts are not particularly difficult ,In general terms the user needs to :-
1. ensure the chosen pin{/s} are digital inputs and not floating
2. enable the appropriate edge detects that you need [eg IOCAP IOCAN ]
3. clear the ioc flags [eg IOCAF]
4. the dt-ints macro @ int_enable IOC_INT will enable all the other settings necessary [GIE,IOCIE]

5. your isr must/should clear the ioc edge flags [eg IOCAF].
also if required examine the ioc edge flag register{/s}to determine which pin{/s} changed [eg IOCAF].
dt-ints will do neither of these things

6. dt-ints can clear the ioc flag [IOCIF] it cannot clear ioc edge flags [eg IOCAF].