That analyzer was developed ad-hoc for a specific purpose a long time ago and then added (or dumped) to the sources. Back then the synchronization relied on different methods, but as you point out using the main clock in the strategy would be the most appropriate path.
Thanks for they reply, sorry for not answering earlier, but I just forgot that I made this question here. I just wanted to write how did I solve it. I finally ended up with extracting those indicators from outer ones and then adding to strategy indicators using bt.Strategy.addindicator() method in the strategy stop() method.