Both are perfectly acceptable English.
Here are some examples of the construction help everyone/those+past participial+bare infinitive. The direct object of help is in brackets, while the second verb (the catenative complement of help) is in its bare infinitival form and in boldface.
In New York after 9/11 the support of family and friends continues to help [those left behind] cope with their loss. (source)
To work together to help [everyone affected by severe mental illness] recover a better quality of life. (source)
More generally, both the to-infinitival and bare infinitival versions are found when the direct object is long.
Some examples of such usage without to, again from published literature. These examples are different from the ones above in that those is followed by a preposition phrase (PP) rather than a past participial:
The central focus of the Block approach to process consulting is to help [those in the organisation or community] make better decisions based on their own resources and understanding of the situation. (source)
There are also heavier weights used to help [those with spastic/tremor problems] continue a task. (source)
And some examples of usage with to:
The effects of these high prices has really caused a lot of debate and discussion in Washington about what we can do to help [those particularly on fixed income and lower incomes] to meet their energy needs. (source)
The main goal of this book is to help [those who are in this sometimes thankless role] to design, modify, and optimize your backup systems. (source)
Then I'll offer eight keys to help [those of you with passive-aggressive tendencies] to find new ways to relate to your anger and to express your needs to others more directly. (source)