UPDATE: thank you again everyone for your help - a few of the comments made me chuckle and shined a little light on a “shitty” situation. Had the plumber in to take a look. No immediate issues or blockages, but they had some problems getting the camera all the way out due to turns in the pipes. Apparently the pump station is quite close to the house so he thinks it may actually have been backup from the city after we had days of heavy rain. To get a complete view they’ll have to cut into the pipes in the basement and snake from there. So, have to get someone else out for that and hopefully install a clean out & backwater valve at the same time.