So here are some scenarios mapped out simply for clinching the playoffs regardless of seed and DIV/WC.
Also this is only 1 team ties, not sure how it works out with multiple teams tied for 1 or more spots, but its pretty unlikely that the Rams, Seahawks, Bucs or Panthers find themselves in a tie with the Bears for a WC spot (where one team is in and the other is out) for a few reasons, mainly that the Seahawks and Rams still play and the Seahawks also still play the 49ers.
Bears go 2-1 or 3-0: Make playoffs because DET already has 6 losses
Bears go 1-2:
-Bears beat GB but lose to SF and DET: One of GB or DET must lose one of their other 2 games.
-Bears beat SF but lose to GB and DET: SF or DET must lose one of their other 2 games OR Packers lose both of their other 2 games
-Bears beat DET but lose to GB and SF: Bears clinch a playoff spot (11-6 vs 10-7 at best)
Bears go 0-3: Only scenario I can find where the Bears get in is the Lions losing their other 2 games, in which case the Bears will have already clinched prior to the Lions game. The Bucs and Panthers both have 7 losses, but they still play each other twice so one team is taking the division and the other is getting at least their 8th loss, unless they tie twice.