Interesting match-up, Itachi wins high diff in both scenario's. V4 and Yata don't really do much for him, Totsuka would but it's not a game breaker. My reasons would be;
-Amateratsu still one shots Jiraiya.
-Jiraiya can be immune to normal Genjutsu via Ma and Pa, but Tsukiyomi would surely kill him regardless of the toads.
-Ma and Pa may help Jiraiya escape Genjutsu, but no one will be helping them escape Genjutsu from Itachi. Itachi takes control of them and has them stick their tongue into Jiraiya's ear, killing him (srs). Same applies for Bunta, he gets put under Genjutsu and kills Jiraiya with Suiton bullets and normal attacks. Furthermore, even if they somehow don't get used to kill Jiraiya, Ma/Pa would be out of control and thus not gather Senjutsu for Jiraiya. And yes, Jiraiya leaves SM
instantly[
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][
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]. Meaning if Itachi decides to cast Tsukiyomi on Ma and Pa, the rest of the fight is Base Jiraiya and one of the elder toads vs Itachi, something Itachi definitely wins.
-Itachi knows the seals of Yomi Numa with full intel and the Sharingan, he easily shunshins away or jumps away.
-Itachi is far faster than Jiraiya, and his Sharingan and duplicity gives him the upper hand in CQC.