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My rims that have the 42c tyres are only 13mm internal width, no issues whatsoever. Rode a cross race yesterday on the same rims but with 33c cross tyres and only rolled the tyre once because I was being an idiot.
Wider rims are nicer but if you don't have them then it won't really limit you on tyres too greatly, after all 5/10/15 years ago narrow rims were the only rims and people still rode cross and mtb on them.
Tl;dr get the 35c kojaks it will be okay. Once they're on the rim they'll probably measure closer to 30c anyway
When mine is in summer touring mode I have some 42c Schwalbe marathon things with reflective sidewalls. So definitely room on the v4 for 35c plus guards I'd say.