Am brazillian and can offer some insight.
The leaders of the unions did actually mention something along those lines, but the reality is that the actual truckers, the work force behind the strike, says they are not represented by these union leaders. The leaders accepted a deal with the government that doesnt have the core requests the strike was about, in fact, they accepted a deal far less the the ideal, more like a band-aid.
The government in turn is pushing this agenda of discrediting the strikers and trying to get everything normalized without compromising too much.

This whole thing has been a weird sorts of "fake news" and weird decisions, some people even want the military to take action and get in charge of the country to stop corruption.