Your IR2 is missing technologies for those poles.
With only IR2 and LEP+ both at default settings LEP+ has no problem finding and inserting poles into techs.
The log looks like this:
1.216 Loading mod LightedPolesPlus 1.7.1 (data-updates.lua)
1.218 Script @__LightedPolesPlus__/data-updates.lua:142: [LEP+] Created lighted-small-electric-pole; light size = 40
1.218 Script @__LightedPolesPlus__/data-updates.lua:142: [LEP+] Created lighted-big-electric-pole; light size = 75
1.219 Script @__LightedPolesPlus__/data-updates.lua:142: [LEP+] Created lighted-medium-electric-pole; light size = 44
1.219 Script @__LightedPolesPlus__/data-updates.lua:142: [LEP+] Created lighted-substation; light size = 62
1.219 Script @__LightedPolesPlus__/data-updates.lua:142: [LEP+] Created lighted-small-bronze-pole; light size = 40
1.220 Script @__LightedPolesPlus__/data-updates.lua:142: [LEP+] Created lighted-small-iron-pole; light size = 40
1.220 Script @__LightedPolesPlus__/data-updates.lua:142: [LEP+] Created lighted-big-wooden-pole; light size = 65
1.220 Script @__LightedPolesPlus__/data-updates.lua:187: [LEP+] found original pole medium-electric-pole in technology electric-energy-distribution-1, inserting lighted-medium-electric-pole into technology electric-energy-distribution-1
1.221 Script @__LightedPolesPlus__/data-updates.lua:187: [LEP+] found original pole big-electric-pole in technology electric-energy-distribution-1, inserting lighted-big-electric-pole into technology electric-energy-distribution-1
1.221 Script @__LightedPolesPlus__/data-updates.lua:187: [LEP+] found original pole substation in technology electric-energy-distribution-2, inserting lighted-substation into technology electric-energy-distribution-2
1.221 Script @__LightedPolesPlus__/data-updates.lua:187: [LEP+] found original pole small-electric-pole in technology ir2-steam-power, inserting lighted-small-electric-pole into technology ir2-steam-power
1.221 Script @__LightedPolesPlus__/data-updates.lua:187: [LEP+] found original pole small-bronze-pole in technology ir2-steam-power, inserting lighted-small-bronze-pole into technology ir2-steam-power
1.221 Script @__LightedPolesPlus__/data-updates.lua:187: [LEP+] found original pole small-iron-pole in technology ir2-steam-power, inserting lighted-small-iron-pole into technology ir2-steam-power
1.221 Script @__LightedPolesPlus__/data-updates.lua:187: [LEP+] found original pole big-wooden-pole in technology ir2-steam-power, inserting lighted-big-wooden-pole into technology ir2-steam-power
1.316 Loading mod IndustrialRevolution 2.3.2 (data-final-fixes.lua)