You can find transcripts of Trump's speeches here:
Donald Trump Southern Border Arizona Cochise | Rev
Your claim doesn't really stack up. There have been occasions, as in the videos you linked to, when Trump is speaking about specific incidences of brutal crimes committed by illegal immigrants (3 in total, apparently). Looking at his speeches, however, he frequently makes sweeping generalisations and enormously exaggerated conflations to refer to huge numbers of people, as here:
"...much more than 20 million people into our country, many from prisons and jails, many from mental institutions, insane asylums, and many terrorists"
What is the basis for these claims, as just one example?
Put together with the reality that the majority of sex crimes, especially involving children, are committed by white, male US citizens (
https://www.ussc.gov/sites/default/...ublications/quick-facts/Sexual_Abuse_FY21.pdf ), this whole immigration mania schtick lacks any credibility. Trump's promise to build a wall ended in abject failure, there is no reason to believe his claim that he will deport millions will come to anything either. Even to any extent that there is any movement towards that, it has close to zero chance of having any kind of impact on the level of violent sexual crime in the US, given that close to 0% of that crime in the US is committed by illegal immigrants.
It's beyond obvious that Trump's rhetoric has the sole purpose of winning the votes of the gullible. What other purpose does it serve? What purpose did his 'build a wall' promise serve? His lacklustre attempts at throwing up a few desultory fences had zero impact on illegal immigration, most of which in any case occurs when people fly to the US and overstay their visas.