Sorry to be slow responding. Your post got lost in the spam folder.
Yes you can combine the two plans. The I&M plan is only strength to you can add aerobic volume in as you can tolerate. The early weeks of the ice and mixed plan may not be too taxing for you so may be possible to add the box steps in the 24 week strength plan without overloading you.
You’ll need to balance fatigue and energy so be mindful but can be done.