group and phot messages not sending to android users

Group messages to Android users are MMS, and require cellular data to work. Wi-fi has nothing to do with SMS/MMS messages to Android users. You have to have a good cellular signal and cellular data for them to work. Looking at your post, you state that your cellular signal is weak or non-existent. That is what your problem is. Your note #5 supports this hypothesis. You need to be in an area with a stronger signal to send messages to Android devices.

Hey there Wmsouthpaw1981,

Thanks for reaching out to Apple Support Communities. I understand you’re having some issues with sending group text messages and photos to Android users. You’ve done some thorough troubleshooting on this so far and I’ll be happy to help.

You mention your cellular signal is weak or has no signal at all. This may be the issue. According to the article, If you can't send or receive messages on your iPhone, iPad, or iPod touch, ‘to send an SMS message, you need cellular network connection.’ In this instance, you may be able to resolve this if you turn on Wi-Fi Calling. 

If this doesn’t have any impact on the issue, go through this link for other steps that may resolve this:

If you can't send or receive messages on your iPhone, iPad, or iPod touch

Regards.

Hey Wmsouthpaw1981,

Thanks for going through those steps. If you’re sending a message to an Android device, it’s already being sent as a text message (SMS) so the option to send as a text doesn’t appear. Did you turn on Wi-Fi calling and see if that has any impact on the issue? If not, you may need to move to a location where your cellular service has better service strength. If No Service or the poor cellular strength is not expected, check for a Carrier Settings update, remove the SIM card, and other steps from this link to see if this helps:

If you see No Service or Searching on your iPhone or iPad

Regards.