Same time for the probes is easy. Same time for the planet is harder.
But if the probes are recording continuously and sending it all back, you can probably identify points that are simultaneous on two tracks, after the fact.
But that gives you just a scattering of points on that day. The next pixel over, for each probe, will be for a different planetary day. Your image, stitched together from all the lines returned by all the probes, is an image smeared over at least as many days as pixels in each line.
But if the probes are recording continuously and sending it all back, you can probably identify points that are simultaneous on two tracks, after the fact.
But that gives you just a scattering of points on that day. The next pixel over, for each probe, will be for a different planetary day. Your image, stitched together from all the lines returned by all the probes, is an image smeared over at least as many days as pixels in each line.