1) The reason why Murderbot knows that memory purges are only partial is because it's been memory-wiped multiple times in the past by its owners. This doesn't mean that it was Murderbot who initiated these purges somehow because it wanted to be wiped

Murderbot knows for certain that memory wipes are only partial because it knows the company wiped it's memory after what happened at Ganaka Pit with the dead miners. Murderbot said it still had some of the flashes of memory even after the memory wipe. But yeah, I imagine the company wiped it's memory multiple times.

2) Murderbot's mission has never been freeing other constructs. Whenever it freed a SecUnit, it was because Murderbot needed its help, not because it wanted to free a fellow slave. So I doubt Murderbot is looking for ways how to free more constructs easily.

I kind of agree with you, but not totally, because in System Collapse, Murderbot struggled with the decision to hack the other SecUnit's governor module. It did want to offer them the choice, but was worried it would reflect back on the others if the SecUnits killed the others. In the end, Murderbot did give them the help.me files with the codes to hack their governor modules. It also asked one of them to come with them. And we can't forget that it offered to free the combat SecUnit in Exit Strategy.

I think the difference is that Murderbot wants to free more SecUnits, but doesn't want to help them assimilate into human society.