To me "Tule" is just a suggestion: "Let's eat." I don't think "have to" is a good translation unless the subjunctive is preceded by a word like "Lazima" or "Sharti", or a phrase like "Imetubidi" or "Imetupasa". Reported.

Literally anything that translates to 'have to' or that has an obligatory connotation will have 'lazima' or 'sharti' or something along those lines

Me too. I remember Tanzanians saying "Tule" before a meal, with the translation given to me as "Let's eat."