To imply that OU Israel is not reliable is motsi Shem rah. To suggest that they accept Heter Mechirah is motsi Shem rah. I have a neighbor who is a mashgiach for the Rabbanut that won’t allow OU products into his home. We have discussed this at length. The rumors he has heard about OU Israel and for that matter, OU would be laughable to anyone that knows the world class organization they run.
The top hashgachos in Israel often maintain standards well beyond what one is accustomed to seeing in the US. But to suggest that OU in the US is acceptable but in Israel they are not is often ignorance or politics.
I have discussed this behind closed doors with leading Yeshivish rabbonim. For example, when I made Aliyah I sat with my Rosh Yeshiva to ask him what standards I should keep. Behind closed doors, he said amazing things about many hashgachos, but he also doesn’t bring them into his home because he wants neighbors to be comfortable eating in his home.
Please do not confuse the issues. There is a reality, and there are rumors and hearsay. Don’t jump to conclusions without doing your own research.