Sorry, not a technical answer, but I feel you need to hear this: if you've been blocked the last thing you should be worried about is if some of your messages are getting through.
Even if your message was delivered, a block is a clear message in itself that they don't want to be contacted by you.
BL3U t1_iu1vfo5 wrote
Reply to Getting a read receipt when blocked? by [deleted]
Sorry, not a technical answer, but I feel you need to hear this: if you've been blocked the last thing you should be worried about is if some of your messages are getting through.
Even if your message was delivered, a block is a clear message in itself that they don't want to be contacted by you.