This map shows all Walmart stores located in Fort Myers ( the new Walmart in Estero just opened up last Wednesday, therefore not listed here). I included the Cape Coral (City of) stores as well:
You see how close the airport (Southwest International) is located. I am looking in particular at two Walmart stores (arrows), that are well visible and accessible from Interstate 75 and from US Route 41. Notice the proximity to the airport.
I am wondering if JR ( and possible CWW) stopped by at the airport to check out the Sievers van! They may have possibly removed (did they have a key?) something from the vehicle. The garage opener for the Sievers house?
With the garage opener they would be able to gain access to the house before Dr S returned home that Sunday late afternoon/night. Ample time to put on the jumpsuit(s), hairnet, shoes, whatever and to hide the dogs away.The dogs may have been familiar with CWW.
They would also have enough time to stage the break-in with the brought-in hammer. If they did the break-in afterwards (after the crime), they could not have not used the same hammer(JR's), unless they cleaned up the hammer, did the break-in and then took the hammer with them.
Before they left, they placed the garage opener back into the van. They may have made a mistake right here.
Breaking into the garage after Dr S had returned home would be just too risky. The dogs could have barked, she could have notified police.
Following her from the airport would have the advantage that they definitely knew she arrived by herself. But then there is the question again, when and how did they get in without alarming Dr S, the dogs and possibly the neighborhood.
Just my opinion of course.
-Nin