The USDA does not advise any home canning procedures without either a water bath process or pressure canning. USDA researched and sanctioned recipes for Tomato products may be found at http://www.uga.edu/nchfp/how/can3_tomato.html. You will notice at that site that there are several recipes and procedures for differing salsas. All but one contain vinegar or lemon juice as an acidifier and therefore may be water-bathed as opposed to pressure canned. There is a warning at the bottom against changing the levels of any ingredients. That indicates how important the acid level is to safely processing by water-bath as opposed to pressure canning and the importance of using only USDA researched recipes. You will also notice that there is on that page, a link to Tomatoes and Zucchini that requires a pressure process. It is unclear whether your have canned Tomatoes separately from Zucchini or if you canned Tomatoes and Zucchini Salsa as one product. Neither one is acceptable in your non-processed condition and the limit on reprocessing a food incorrectly processed is 24 hours. 
Sealing of jars, which is required to maintain safety in properly processed canned food, is no indication that all microbes were destroyed during the process. A vacuum forms merely from the fact that hot contents inside a closed jar cooled to room temperature; that is what forms a vacuum (seal). Reaching the proper temperature and holding for the required amount of time is the only assurance that deadly botulina spores, which need no-oxygen and non-acid conditions to grow, were destroyed in the food and therefore it is safe to be stored without acidification or refrigeration.

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