06 Explorer transmission reverse band is used for 1-Lo as well as Reverse? on 2006 Ford Explorer

my 06 explorer will not move when shifted into reverse. I have done mass amounts of research and come up with many diagnostics ranging from complete tranny rebuild, Servo Motor, Solenoids, or even something simple as fluid level. Question is...If the truck drives fine in 1st gear (same BAND is used for forward and reverse), could I eliminate the reverse band as an issue?

Asked by for the 2006 Ford Explorer
yes but you may seek a free diag and est from aamco
aamco is the one who told me I needed a complete rebuild. I brought it in and they had a "non-professional" drive it around the block... and that was the extent of the diagnostics. I was told that he hooked up an onboard tester that detected codes as he drove (for literally 5 minutes). They brought me out back and showed me what a reverse band looks like, and told me that I needed it replaced. All in all, I would like to know what to check next if I can eliminate an entire rebuild. I have been told "Seervo-Rings", Low Fluid Level, Solenoids, etc...Oh, aamco also said that my fluid level was low, but never actually checked it nor did they bother to mention it to me? a tech that was not there when I brought it in read the report to me and thats how I found out the fluid is low.
get a 2nd opinion